Thanks for an excellent explanation of cooling and related issues in IC engines. I also fervently support you in your quest for improved understanding of scientific principles in the general population. I don't mean this in any condescending way. The scientific method is the only way by which understanding of the world around us can be gained. The quicker the education system is oriented towards this end, the better it will be, I hope! Anyhow, many thanks for an enjoyable discussion.
@@ldmtag Shittoir, similar to Pissoir. Shit*twa, Piss*wah. These tutorials should be mandatory for schools, language may require a bit of editing for swears, would also be useful for remedial spelling and punctuation. 😆😂
One great thing owners can do is wash the rad. Quite a few years ago I was helping a mate move house up to the Kahncoben area in one of the hottest days of summer on record. His trucks temp rose to just outside the red zone, but not into it. It never missed a beat , and on the downhill it dropped back rapidly. He was concerned. As someone who has raced and rallied cars for a short time I wondered if the rad was plugged up from the outside. His hilux was immaculate but he had never hosed the rad and air con condenser . We soaked it when cool for about 10 mins then jet washed . An unbelievable amount of slurry and seeds and bits of bugs came out. The upshot was on another journey in the same heat the temp rose just a little and and the air con he said was better and the truck seemed quieter. Anyone remember locusts across Victoria and cars boiling at the roadside ?
Great tip, I agree. Another tip is to straighten any bent fins on the heat exchangers since they block airflow. There are "fin comb" tools available to make this easier, but a pocket screwdriver and some patience works great too.
I remember one trip down the Murray valley highway in summer 1975. You had to stop at every servo to hose out the locust slurry. The locals had rigged flyscreen across the grilles which sped up the cleaning process.
*Roadside BBQ locust sammiches? Homemade French locust soup? That sounded pretty scary. Any loss of traction, skidding, from all the locust goo on the pavement? During mayfly hatches in Wisconsin, many bridges are closed and have to be plowed and sanded come daylight because of the huge amount of dead mayflies. They also show up on weather radar. Outside in the streetlights, it looks like a snowstorm. 😲
The way I learned the difference between heat and temperature is to picture two boxes in front of you, one containing air, and the other containing water. Both boxes are at 100 degrees Celsius. Now stick your hands into both boxes. The one with hot air will feel uncomfortable for a moment, while the one with water will scald you. They are both at the same temperature, but the box of water contains much more heat.
@@mini696 What do you mean they didn't teach him well? Water has approximately 980 times more mass than air, therefore for the same volume of water and air at the same temperate, there is a factor of nearly 1000:1 difference in heat energy. Remember, ignorance is bliss, right up until it isn't!
What differs is the amount of energy in them. Why do you feel a difference? Because different materials have different thermal conductivity properties. And what also is part of this is that your skin evaporate water to cool it down in the air. Of course not possible in water.
My bull bar saved me last night. A roo jumped out last second on a single lane gravel road deep spoon drains both sides I was traveling at a safe speed nothing I could do.
@@arcrides6841 saved me money saved any damage saved any chance of being stuck in the middle of nowhere with no phone reception.... so could say it potentially saved my life too. I will just also say that John saying you should drive better and not hit kangaroos should be doubled down and drive better and not have an accident as well lol
@@arcrides6841 also I'm not from a city nor do I travel to one in my ute there is reason I have a normal car for that there is a time place and reason for bullbars 👍
Many yrs ago where I worked, we got new machines with Cummins engines. They were equipped with thermo fans that came on around 90 or 95c. The mechanics fitted override switches as in their opinion that was too hot. My opinion was I think the manufacturers know the range they want for operating temp!
But that one time crossing DP Creek towing max weight on a scorcher day....and the computer fan controller goes phutt..... and the driver is awake and scanning his guages... maybe..just maybe......
95C is too hot. 85C (185F) is ideal here in America while towing. You want some buffer in case you run into a situation with reduced air flow, like stop and go traffic
@@Noah_E : sorry Noah, did you watch all that - if~ 130C is the "upper range before some venting occurs.. 85 isn't even at coffee brewing temp, let alone approaching the danger zone... 125kpa (mine is 1445kPa 21 PSI)- over atmospheric / gague pressure... Opinions don't matter in the face of evidence (the empirical knowledge base is extensive). -America Europe, Asia or Australia - facts remain.
This was well timed. I just did coolant service and out of curiosity I monitored my coolant temps via ODBII and got all these same consistent numbers so now I'm happy after watching this that my coolant system is running perfectly.
Geeze John, vehicle temperature gauges are very reliable and accurately tell you three things: 1. The engine is not up to operating temperature. Advice is don’t cane the engine during this time. The gauge reading rises during this phase 2. The engine is within it operating temporarily range. Typically 85 or 90 degrees through to around 115 or 120 degrees. No problem keeping your jandal down. The gauge reading is steady during this phase staying in the normal range 3. The engine coolant temperature is increasing above the normal range. The gauge reading starts to increase and moves into red. Advice is to back off the power. Dingo Piss Creakians sometimes get to 3 early when they forget to remove the blind they put in front of the radiator before crossing DPC.
@@Wdeane1957 I really have no idea of what will trigger when, but there is no special light. you know, modern digital car (Volvo V90). So a message will show up telling me something, and the car will also adapt the system to not overheat, like restrict engine functions and similar. Sensors all over the place, and of course electric fan that goes on when needed and i guess they will automatically also restrict ac, maybe? Never had any issues, the system just works. Even when we had 30 degree C, full cargo and drove 470 km. No issue what so ever. Pros and cons of modern cars - the computers handles stuff for you. The bad side of it is that you have no idea of how it is programmed and what triggers when and how, and which parameters needs to be on a certain level and so on. The same for gearbox of course, and torque converter. It handles stuff by itself. And even when parked, if the car thinks it needs to cool down engine more, it will do that automatically. You stop, turn engine off, lock the car and sounds will still be heard under the hood. Electric water pump, electric shit everywhere. =) Just unlocking the car and open the door makes a lot of funny strange noises appear under the hood.
@@Xanthopteryx 30°C is fairly mild here in Australia. I've driven through outback Queensland in 40-43° heat for 7-800 kms and thankfully my car (4WD loaded with camping gear) does have a temperature gauge, but for accuracy I also use a digital gauge that connects through the cars OBD2 port to monitor the precise temperature. I've seen 106° but that was up a hill and it soon got back to 86° downhill and less engine load.
@@Wdeane1957 I know, here in Sweden that is kind of hot, but instead we also have low temperatures. Record low in Sweden is -52,6 degree C and record high is +38 degree C. A normal year where i live can go from -20 (some times -25 and in a few occasions -30 C) and then +25 to +30 (some occasions up to 33-34 C). So in one year we can have 60-65 degree C difference. That is also a struggle for the car, i can tell you. But, it just works. People here are towing caravans during high heat summer too. Older cars tends to sometimes get in trouble but modern cars with all their sensors alert in time and handles it better.
Interesting, perhaps Mr Triton should also consider the location of the temperature sensor on each engine and also the thermostat rating of each engine. The thermostat in the Hilux might simply open at a lower temperature where as the Triton might need a higher temperature to help with emissions. I have had 5 Land Cruisers over the last 40 years and they were all fitted with a bull bar and I have also done my fair share of remote camping trips. In all those years I have never hit a kangaroo so when we purchased a new Sahara in 2020 I didn’t get one fitted. My friends couldn’t understand why I feel I don’t need or want one. They always ask “but what if you hit a roo” and my answer is “that’s what insurance is for” I also add that I would feel a hell of a lot better hitting a roo without a bull bar fitted than hitting a child that runs out onto the road with one fitted. Something for the urban cowboys to think about. Cheers Stuart.
At TAFE we did a bit on Boyle's law, where it is stated that water boils at a higher temperature under pressure. This is the reason a vehicle's cooling system is under pressure from the radiator cap or on newer vehicles the recovery reservoir. When the drivers look at an analogue temperature gauge the centre part of the gauge is the most accurate.
Just putting this out there. Different engines will have coolant sensors in different places. Whilst it is possible that engine oil temperature (from directly inside the pan under the crank) may be a ‘more level’ playing field for comparing engine temps, it’s also well-known that different (types of) engines deliver their best power, efficiency and longevity whilst indicating different core and fluid temperatures at any 'simmilar' point of or between the sampled engines. The engineering and configuration is just different. An apple and a pear are sameish, but different, and both will sustain you.
@25:35, Spot on! There's a reason the factory (oil/coolant/AT fluid) heat exchanger is in the circuit. It’s to modulate the AT fluid temperature. Just like a coolant circuit thermostat, its job it to assist in keeping the fluid passing through it within optimal operational parameters. Thermostats and heat exchangers are there to facilitate both warming when needed, and cooling when needed. Modern ATs are very specific about the frictional qualities of their fluids and those fluids are only “in spec” when they are within the designed operating temperature range. Almost any AT on the road now will have a ‘brain’ and whilst it may compensate when its fluid is outside of its preferred temperature, it will not operate optimally until it reaches the correct temp range. You really always want that fluid up to temp ASAP and kept “in spec”. Interestingly there are ATF ‘cooler’ suppliers out there that state to bypass the factory heat exchanger. In my book, that’s just asking for trouble in cooler/cold operating conditions.
Thank you very much. I didn't want to get into this issue in that detail, because people are always telling me the reports are too long, but that's exactly what I was alluding to.
There are some cars where bypassing the standard cooler is a good idea if you don't want to be bringing all the boys to the yard (transmission) with the devil's milkshake. Think Falcons with a Barra and ZF auto. The standard cooler is so egregiously and atrociously flawed in its design that it overcools the transmission fluid, keeping it below temperature for twice the amount of time that ZF recommends and also likes to just split, without warning, introducing water to your auto. In this latter situation, the specific heat capacity of the water, while impressive, is unfortunately insufficient to prevent certain parts of the transmission melting and/or galling and welding themselves together. Most kits that you can buy for these cars have a fluid thermostat and thermostatic fan switch, so they do more good than harm in most cases. You just have to use your brain when purchasing/fitting/talking to your mechanic.
FRICKEN AMAZING episode! I followed along perfectly and clearly the whole way through. The way you explain things is like my dad used too; solid facts, real life examples, direct. I really enjoyed this topic also as it is something i would think about it when driving through 40C !
I recently upgraded my v8 landrover motor from the 100hp military unit to the 180hp Stag motor one. A few years ago I rebuilt the military 2 row radiator to a 3 row core. Even driving "giving it the willies" in deep river run gravel in low ratio 4wd the radiator temp never goes over 90 deg. I run standard 50/50 coolant and I suspect that its still withing the proportional control of the 85 deg thermostat. Good job explaining thermodynamics to your viewers. You did a fantastic job. I spent the first 10 years of my career as the design engineer for a boiler making company, so I appreciate the effort you must have put in with these questions.
FYI, most manufacturers hold the temperature needle in the middle of the gage anywhere from 66 degrees to 100. The computer tells the needle where to go .
I have a 1999 AU Falcon and it was running 'cold' all year round, I changed the radiator cap 3 times and had very little difference in temp, I felt the optimum operating temp should be higher... so I replaced the thermostat again and sealed the unit and temp rose a couple of degrees, yay...up to proper temp. In my 2016 BT50 the 'high speed' fan didn't cut in climbing a hill with AC at flat chat and 3 kids onboard and it went well into the red line and power dropped like a bride's nightie, needless to say we crawled up hill as I shut the AC off, wound down the windows and put the heater on flatout with the fan flat out and lo and behold the temp dropped power picked up, I did a U turn and rolled down the hill I was just climbing, all the power came back so I put the AC back on and took it steady driving home, 2 days later the Local mechanic replaced the clutched fan. No issues since. So just a trick that's saved me a couple of times is to turn the inside heater fan on and flick the heater unit on to get the temp down fast! Thanks John...
Why slow down? Drop down a cog and the engine viscous fan slould suck more air across the convective cooler... or the electric fans should kick in if working properly....
Brilliant sciencey stuff, I love the explanations and the DEPTH. I was getting a bit heated pulling myself and my 2.7ton van (3.0 Isuzu) while climbing the Clyde on Kings Hwy with my roo bar blocking my airflow. After watching this beautiful description with voiceovers I am heading out to drop my glycol ratio to increase heat transfer and remove a bash plate restricting air flow. Thanks for that mate, I also liked and subscribed! Love your work.
Hi John - Great video - as an engineer who has worked in heat transfer / thermal management for around 25 years, I feel that you have done a fantastic job of explaining the topic - a topic that most technical people struggle to get their heads around. In fact, I am considering getting my engineers to watch it as a training video… Other things to consider with the 4x4 comparison: 1. The coolant temperature is often linked to the emission controls - ie combustion temperatures need to be controlled in a relatively narrow temperature range which means that coolant temperature (particularly around the head) can’t vary too much. (Many industrial engines de-rate engine output once the coolant temperature exceeds their maximum design point - for example 107 or 110C). Maximum operating temperatures vary from engine design to engine design. 2. Different engines have different coolant flow rates - this varies significantly from manufacturer to manufacturer and just measuring the coolant temperature can be misleading. 3. I might have missed it, but did you mention the thermostat? Many thermostats start to open around 90C - unless the thermostat is removed and the by-pass blocked, any coolant temperature measurement below at least 95C is probably not representative of full flow through the radiator. 4. Finally thermo-fan control also influences coolant temperature - fan control (along with the thermostat) is used to manage coolant temperature. Whenever the AC is operating, at least one thermo-fan is operating regardless of engine load / ambient temperature, and this further influences the coolant temperature. Thanks Derek
Good work John! Not a bad effort, yet again. There's one thing that would affect the operating temperature range very considerably between the two different vehicles, that I didn't notice you mentioning (sorry if I missed it because of the noise I had in the background while listening to your video). The thermostat. The chance of the two test vehicles having thermostats with identical operating characteristics is virtually zero. For instance, the factors involved in thermostat design include (but aren't limited to) initial opening temperature, fully open temperature and flow area, whether there's a warm-up recirculation circuit (including initial and final closing temperatures and flow rates), radiator circulation bleed area (allows some flow through the radiator, even at low coolant temperature), linearity (or otherwise) of the flow area increase from closed to fully open, etc, all of which will considerably change the coolant temperature at any set of engine operating conditions. Powertrain cooling systems have been one of my areas of particular experience while I was a warranty engineer (ie: finding and fixing the mistakes of other engineers after customers have experienced problems) for two OEMs. I can back up your assertion that the temperature gauge calibration is deliberately made to leave the needle in a position that won't potentially alarm the driver, as long as the engine's temperature is within acceptable limits. However, the gauge is also usually calibrated to frighten the brown stuff out of the driver if the temperature starts creeping up too high, so the driver will be more likely to pull over and let the engine cool down (after all, going outside acceptable limits is, by definition, unacceptable). My advice to the man with the question is to perform all due-diligence checks and maintenance per the book (if not, a little more often), and just drive the vehicle. It sounds like the temperature gauge is doing exactly what the manufacturer calibrated it to do. From my point of view, as long as there are no coolant leaks, bulged or worn hoses, emulsified water/oil mixture, or white semi-powdery substance build-up at the ends of any of the coolant hoses (caused by weeping of the hoses and/or hose spigots), there probably isn't a lot to worry about. Bulges or wear in hoses can burst, leading to catastrophic engine/transmission failure, and the bulges are often, but not always, caused by electrochemical degradation of the rubber hoses. The white powdery stuff is an indication that there's either a hose that has a pin-hole into the webbing layer, or a plastic radiator end-tank hose spigot is deteriorating, and potentially about to dump the coolant (if the plastic has discoloured or started pitting, it's on its way out). Emulsified water and oil can be a multitude of expensive problems, including a leaking in-radiator transmission fluid cooler (requiring an absolute minimum of flushing of the transmission and engine, possibly also replacement of all coolant hoses due to chemical degradation from contact with the oil, and maybe even transmission replacement). Note that aftermarket transmission coolers might not have been adequately pressure fatigue tested (there are usually high-frequency pressure pulses in the system that many people don't know about - been there, seen dead transmission coolers before, especially in cheap knock-off radiators). Then there's good-old machining chips, that somehow haven't been removed from the engine's manufacturing processes, that can get stuck in radiator and heater core passages, fretting away until they wear holes in the tubes. Oh, what fun coolant systems can be when something goes wrong! 😉
One thing I have noticed when using a obd-II scanner is to take into consideration the "Coolant Temp Commanded" by the ecu as well as the "Coolant Temp" in addition to the "Current Oil Temp". New diesels tend to run hotter for greater efficiency and the engine oil needs to run (generally) at around 105-110ish to ensure that impurities such as water in the oil is dissipated out through the crank case vent. 100deg under load uphill is fine. Wonder what % the cooling fan is running at - I would lay odds its running at only 30-35%.
Another reason for the difference between the Hilux and the Triton. If the Hilux is substantially older - think pre-DPF - then its design operating temperature will probably be lower than a new engine designed for improved efficiency.
It's interesting to watch my Edge CTS3 telemetry screen. With my 6.6 litre Duramax V8 diesel, one of the huge number of parameters I can choose to monitor is the cooling fan rpm. This cooling fan looks like a typical viscous type. However, it has an electrical connection as well, and there appears to be a method by which the ECM can vary the rpm. This can actually be done to the point where the fan rpm is higher than the crankshaft rpm. Go figure. Most of the time, though, the fan rpm is very low.
Two things come to my mind. 1. When measuring water temps it is important whether it's the temperature of the water leaving the engine respectively entering the radiator or leaving the radiator. I would consider 110°C leaving the engine perfectly fine but 110°C leaving the radiator rather hot. 2. Modern engines tend to run hotter for better efficiency. Some engines run at different temperatures in the cylinder head and in the bottom. Some other engines vary the temperature dependent on rpm and load.
One of your best videos. Well, when it comes to something I'v been chasing for a while now in an older prado trying to keep it under 100deg calluses when towing thanks Jhon for great content very much appreciated...
Have you ever taken the radiator to a good radiator shop and had them take the top and bottom tanks off and physically rodded out the tubes? (Plastic top and bottom tanks alloy core) If it's an all aluminium welded radiator it might be cheaper to replace the whole radiator as cutting into them if they are of all welded construction is not recommeneded. Also is your fan a viscous coupling one as they can leak out the silicone thus reducing their efficiency by "slip" so not drawing ther needed volume of air through the radiator? (Toyota sells the silicone for you to put in the hub to restore it) If electric fans...are you sure both fans work and are being "switched in" under load?
My turbo hatchback runs at 90C summer or winter, gains about 5C when you cane it, drops back down almost as quick when back at normal cruise. My previous car sat at 72C, so there's no "normal" temp for a particular type of vehicle.
Excellent explanation, as usual. I was ecstatic when you covered the difference in specific heat between water and a 'coolant' mix. But do you think old mate's going to get it, or is he perhaps going to suffer a cerebral haemorrhage trying? I certainly hope his personal cooling system is up to scratch too.
My old commodore ute would start to over heat towing my ski boat on a hot day. I'd get to an intersection halfway to the lake and then accelerate back to 100 and then watch the temp gage rise from half, to the red zone (if I didn't take action). So what I'd do was 1; AC off (temp would still climb) 2; window down. 3; heater and fan on full ! temp would drop back down to halfway on the gage. Amazing how much the heater core could contribute to the cooling of an engine that had a radiator blocked with bugs! I never did get around to cleaning the fins out on that one, but I made sure I put some fly wire in front of my current one.
Fly wire actually forms a barrier (quite a substantial one) to all airflow...... so you are reducing the cooling available to your radiator... and probably more than say the effect of one month's worth of bugs. As you indicated.. cleaning the radiator of bugs say once a month would keep the radiator airflow where it should be... (I have seen those flyscreens or equivalent stainless steel mesh used where 4wd bush bashers were pushing through wild grass areas at seeding time for those plants....and they are definitely good for catching those seeds before they plug up the radiator fins in mere minutes!)
My 3 HJ's were the same. They were fine until they were under load, then the cooling system would show itself for all it was worth, not much. I miss Australian manufacturing, I don't miss what they manufactured.
@@JohnSmith-yv6eq yes the fly wire acts as a barrier, but it catches the bugs right at the front and allows much easier cleaning. I’ve never had to turn the ac off and heard on since 👍
@@davidbrayshaw3529 I was talking to a radiator shop about replacing a broken radiator with a fancy one. He said don’t bother. He’s never seen a Holden (later models at least) overheating that wasn’t because of a clogged up radiator.
Thank you so much for doing this episode. This was so good to know as I do keep an eye on my temps when towing. Your explanation, including the glycol mix was great to learn. Excellent information explained in terms I can understand. Probably the most beneficial episode for me that I've watched.
ironman bullbar blocks the lower section of the airflow. most modern diesels run at 90 deg and using a ob2 reader it will most likely read more than 1 temp reading and often not the one that is connected to the temp gauge. the VW amarok has 3 temp sensors and the gauge will read 90 but the other 2 will read between 80-108 when working hard. If you fit an extra probe to the top radiator it reads 90 so the gauge is the exit temp. The cooling system is working as designed and different parts of the motor produce more heat than others like the block but once the coolant flows around and reaches the thermostat that only opens at a pre determined temp eg 90 deg I feel the oil temp is a more important indicator on when you should drop back a gear and slow down once you get over 128 deg coolant temp 110 deg slow down as well
I'll add two bits of info. A radiator cap doesn't control normal running system pressure. In a typical cooling system the designed running pressure would be about 6-8 psi. The cap would release at the rated pressure to release in the event of over pressure due to various not good scenarios. Also, too much ethylene glycol used as a coolant in concentrations over 70% will actually reduce the boiling point, go figure !
You remind me of some of the TAFE/course instructors I've had over the years . I'm in aviation engineering, and have always maintained my own vehicles . I enjoy your videos, and the wealth of information - keep it up.
Our Land Cruiser 200 will run at 85/86 all day on the HWY at 110km/hr,whether it is 5 degrees outside or 40degrees.Hills it may get up to a tops of 90 degrees which drops off very quickly once at the top.Towing,GCM of 5T,around 87/88 degrees at same speeds on HWY,max on a big hill i have ever seen it is 93 degrees.Auto fluid temps seem to rise about 8 to 10 degrees when towing.
Thanks muchly for the vid, very informative and useful for me as I have just started towing a 2.5T caravan and also recently acquired a ScanGuage. Having said that, whilst I love looking at all of the live data, I really don't know what they either mean or what is good and what is bad. With regards to my engine temps, I figured out that the ECT, (Engine Coolant Temp) has become my focal point while towing. Ironically, I too have a Triton (MQ), I find that my non-towing ECT sits around 85-90C, while towing, I have seen it max out at around 102C, which to be honest made me a little nervous. However, after listening to your explanation, I feel somewhat more comfortable that hitting the 100C or just above is well within what would be a reasonable temp threshold. Thanks again John.
Spot on with your comment about a turbo being a heat exchanger. In a Nissan Patrol I used to own, I installed two thermocouples; one in the manifold and the other in the dump pipe. Under full song, the temp difference between the two could be as high as 200 degrees C. It is for this reason that I drilled and tapped a hole in one of my manifolds on the 6.6 litre Duramax V8 in my 2012 Silverado 3500 4x4.
Another really informative video, thanks John! I load up my Pajero Sport and go bush all the time. The temp gauge never moves above 'normal' but my scan gauge reads 100-120°C all day and night without any problems. I use the Mitsubishi coolant and replace it as per the maintenance schedule.
Great video John. I've got a TD42 Patrol and have had the temperature guage on the "H" up a big hill fully loaded. The Watchdog read 105° I pulled over and everything was fine under the bonnet. If anything it was running better at that temperature. I wonder if that's why the Triton runs a bit hotter, to make it more fuel efficient?
In marine applications the units with header tank heat exchangers were always 2 to 5% more efficient on a grams per Hp hour rating. The ones that ran salt water with anode protection were 20% cheaper to buy but otherwise identical. Example Yanmar 3GM30 vs 3GM30F. The water jacket temperature difference was 60C vs 90C
All the TD diesel engines have a design fault where they run warm under load, the TD 42, the TD 27 that's why Nissan never released a turbo version for a long time, and when they finally did it was a low boost, and if you doubt me, ask someone who aftermarket boosted one and then used it hard what happened ( or google it), the head was simply not designed to disperse heat well.
All very interesting but you overlooked the importance of an EGT ( Truckers call it running on the Pyro) and there is a good reason. I cooked my Isuzu by pushing it too hard for too far up a long central north island main road. Very expensive . Had I fitted the EGT that I had sitting at home I would not have run the exhaust temperature high enough to overheat the oil and effectively turn it to water eg non lubricating super low viscosity overheated oil pumping around and not lubricating anything. I recon that exhaust was running at >800C for >20minutes based on my subsequent use and observations from running the rebuilt Motor C/W EGT . where I run it at 350-550C for most driving and under 600C for long hill climbs and allowing a brief peak of 650/700 particularly when towing. or as a 4x club member did . Drove home at motorway speeds not knowing his front locker was stuck on lock. the extra load from continuous wind up together with a long engine killer hill near home seized his engine and the front diff caught fire. (put out with a compulsory carried powder fire extinguisher (club rule) The rebuild engineer commented that the oil was as thin as water. For both instances Interesting that when the engine seized the water temp gauge was right on the middle normal temp I assume around 88C. My understanding is that modern common rail diesels will shut themselves down if the predetermined max oil temperature is reached then Enable a restart when the oil cools down. So fit an EGT or an oil temp gauge if you are pushing your wagon and want to know it.
Informative video once again from bogan beard striker. Few items with video. 1. Triton has the worst towing due to the position of rear wheels. Any load on tow bar lightens the steering. So your item of evasive driving isn’t as effective. 2. Mitsubishi sell bullbar as standard option when you purchase a new vehicle. If they effect the towing then they wouldn’t have them as an option. 3. Bullbar, maybe in your state Vic & NSW you don’t require them. Come over to WA & NT you may change your mind. Idea of bar is to protect the radiator & lights so in remote outback you can get home. A light alum bar is a good accessory, not the heavy cow scraper bars. Keep the videos coming there good education for outback wonders.
Thank you John. I enjoy the scientific, systems thinking you provide in your videos. Here are a couple comments for the discussion. 1. Based on your explanation, any difference in the ratio of water to coolant between the two vehicles will also contributed to the observed water temperature differences. 2. The process of planning trips to limit the amount of driving at dawn and dusk will reduce the risk of hitting a kangaroo by avoiding the times of greatest macropod activity, and therefore the probability of encountering Skippy altogether, before even needing to rely on your defensive driving ability.
Great video and really valid points, could it also be connected to the different thermostat specs ? Google suggests that Hilux opens at 82 and Triton at 91
Here in New Zealand it was inevitable on any hot sunny day during the holidays to see a Holden standing at the side of the road caravan in tow, wife and kids standing around and the man staring forlornly at the steam geyser issuing from the radiator neck after he had undone the cap because the car "overheated".... GM was well known for only providing a radiator that ony just coped when brand new and the temperature was "average"......
Spot on. I’d also add that it is likely that the modern Triton engine is working more efficiently (converting chemical energy to effective work in a smaller combustion space, with less surrounding radiative mass) ergo likely to be lifting the temperature of the combustion process and surroundings etc, than is the case for an older lazier Lolux. Similarly the design of the liquid-to-air (“radiator”) of the more modern Triton will be seeking to do more work (exchange of energy) with less metal, less circulating fluid, less mass overall and probably smaller radiator assuming all other things equal. That is the Triton is likely to have have a more efficient cooling system design from the perspective of mass etc, therefore will NEED to operate at a higher temperature than the Lolux. Adding an auxiliary cooler will undo aspects of design by adding mass, complexity and points of potential failure. I also dare say the manufacturer’s specification for lubricating oil in the case of the Triton and Lolux will match the design envelope of the operating temperatures. I suspect the oil spec of the Lolux would not meet the requirements of the Triton - no surprise. Going to your bullion robber analogy, the guy carrying 24 bars would be sweating like a pig, but still be the man to depend on.
Hey John , one for comments driven trucks for a few years 35 plus . CAT engines running temp 100 c , most EURO trucks 95 C so running at 95 should produce a more efficent combustion ? Great two videos ( sorry about spelling ) Cheers Chris
I had a problem where I couldnt go up a hill towing on a hot day without the coolant hitting 105 and my AC turning off. It was fixed by changing the viscous fan hub to an aftermarket tru flow hub. Did the same hill with the same trailer in same weather conditions and it didnt go above 90 degrees. The factory hub was designed for fuel efficiency and didn't kick in until 105. Not good when thats when the AC its turned off it stinky hot conditions. Id rather lose fuel efficiency for a cold AC and cool engine
See “Charles Darwin boiling potatoes in the Peuquenes”. The book is “Voyage of the Beagle”. The nearest high ranges are above 7500 feet which isn’t high but enough to mess with boiling a spud. He seemed a bit glum about boiling a potato for 24 hours only to have it as hard as it was when first put in the pot
Milk first tea or coffee. Agree with your point but in the example the hot water fucks the first milk added, but if you do hot into cold it tempers the milk better
Yes. Perfect explanation. As long as the cooling medium is still present, there is no real problem. Not sure where the coolant disappears to if you top up your expansion tank. My vehicle gives a level. If I fill to the level, a week later it’s just below the bottom indicator. It doesn’t go any lower between services. Should I not top up to recommend level?
Totally agree with your tutorial here. I wonder if you could do one on auto tranmission temperatures and at what temp is the auto about to have a problem.
Synthetic trans fluid is good for 275°f (approximately 135°c) this is it's breakdown point where the fluid starts to degrade quickly and can cause damage. My truck's computer puts it into limp mode if the trans hits 265°f.(I've never seen it, that's just the manufacturer's settings) most I've ever seen was 115°c on a 30°c day pulling a 2.5t up a steep grade while merging with highway traffic.
This used to madden me as a mechanic. If the temp gauge is in the normal range, (barring some extremely unlikely specific fault) then the engine is operating at the correct temperature for that vehicle. If it goes into the red or things start beeping or flashing at you, that's when you have problems.
My physics teacher at high school asked the same question as you regarding when to add the milk to the cup of tea. I always thought adding it later was the way to go. He actually said it made no difference!
Back in my auto instrument days we used to regularly recalibrate temp gauges for Mitsubishi dealers to make them read a tad lower. It solved a psychological problem for the owners who drove the service departments mad. The owners would not believe that their uses/vans were not overheating.
Hi John, Great video, loaded with important fundamentals. Although I wish to highlight that I have a different assessment of the "hard ceiling" of the temperature range. The thermostat reads an average of the water temperature in the water jacket, not the maximum temperature adjacent to any hot spot in the head. The hard ceiling is the temperature at the hot spot, not at the average temperature. We need to have some buffer between the temperature reading and the boiling point of the coolant. Should we rename the radiator to "convector" It may take a while to catch on. Cheers.
The coolant temp gauge has been irrelevant for years, probably decades for some manufacturers. It used to fluctuate according to the actual temperature and had the numbers of the readout printed on the instrument. With skills diminishing, cars becoming more precisely engineered and more of an appliance, manufacturers decided that instead of teaching drivers to monitor the instruments it was easier to make the needle stuck in the middle for the whole range of the normal operating temperature. Nowadays, the temp gauge does not exist in many cars and instead there is a blue light for cold coolant, blank for normal and red for high temp which I think is a better approach to the meaningless stuck in the middle gauge. Personally I think having a number of instruments to monitor, like generator output voltage, oil pressure and temperature, vacuum etc in a vintage car is part of the appeal. You are connected to the machine and operating it rather than sitting on a sofa with wheels and the computer telling you what you can and can’t do.
I do not have a gauge and no light either. Volvo V90. And my oil stick is digital. And if coolant level goes too low, it will tell me. If engine goes on too hot it will tell me and reduce power. If gear box goes too hot it will tell me and reduce power. I also have a coolant curtain(!) that opens and closes depending on some... factors. Makes for less drag when driving if it is closed. Keeps heat better in cold weather. And so on.
Hi John, the supposed temperature difference between the hilux and trident could be as simple as the thermostat. In most cases they start to open at about 82 deg c, fully open at some higher temperature. They are relatively basic and it would not be surprising to find a 5 degree difference between two new ones let alone one new and one old at fully open. That is if they are in fact specified at the same temperature, which they often are not. Pop into supercheap for a look. P's I apologies for my poor Grammer and punctuation in advance. Kiwi you know. :)
Top hose at 108C isn't the end of the world with a pressurized system. Get yourself a copy of thermodynamic & transport properties of fluids (it's a book) and see the effect pressure has on boiling point. The hotter the coolant, the smaller the rad can be, with aero and pedestrian protection benefits.
Hi John, another thing to check is the routing of the transmission as mentioned by you. Climbing a hill will create heat in the oil and transfer some of that into the Coolant. My Pajero is a bastard for doing it. Regards
Hi John, technical description, TERRIFIC! Expat Australian living in Phuket Thailand, ALWAYS watch your videos, feel free to visit us in Phuket. Best Regards, M
Have had an AU Falcon cut the aircon when I was towing at 80kmh..... on a straight slightly sloping road... and down in second gear already.... how slow do you want me to go...
Acording to my book on diesel engine design the problem with diesels is preventing over cooling as they tend to run too cool for optimum fuel efficiency and oil life.
I have a curtain in my Volvo. It is closed when engine is cold and opens if needed by engine or ac system. And it also makes the car get lower consumption since when closed there is less air resistance. Pretty funny that curtains was on like all cars before, then removed, and now back again.
Just did 3,000km up and down the Great Dividing Range at 3 different locations between Qld border and Lithgow/ Katoomba, in a manual 2019 MR Trition towing 2.3t, seats full, 180kg ball download and 350kg in the tray. Had zero problems. Sounds more like an engine understanding issue. Failing that it could be a user, gauge/sensor, thermodynamic understanding or a maintenance issue rather than a Mitsubishi design fault.
Great explanation as usual, I agree about the safe temperature range. I do respectfully disagree about installing a transmission oil cooler before the heat exchanger in the radiator being superior for the reason you stated though. Every automatic transmission vehicle I have seen with a cooler integrated into the radiator was designed with the cooler in the COLD side of the radiator, which doesn't necessarily warm up very much or at all in cold weather. That's a very common misconception. If you feel the lower radiator hose after driving around town on a cold day, you will likely notice that it is actually cold! Every OEM cooler setup I have seen with a heat exchanger integrated into the radiator and an external cooler placed the external cooler after the radiator's cooler to return the coolest oil possible to the transmission. Manufacturers have recently started to use thermostats to block the flow through external coolers during warm up as well as oil to coolant heat exchangers fed by the hot, thermostatically controlled side of the cooling system to regulate the transmission's oil temperature, solve the problem of overcooling the transmission, and improve fuel efficiency and cold weather performance by getting the transmission warmed up faster.
My apprenticeship was spent chasing overheating buses and cooling them off etc. The dealer would have tested the coolant glycol %, and the fan. There's not much that can be done except fitting a colder thermostat. Gearing down makes a huge difference on trucks when they have a weak clutch fan, on a hill at 60+ it will be getting into the actual red until it kicks down as well as the auto going over 130°c, despite that running a separate cooler and electric fan. I've also watched the gauges on enough European trucks for oil temperatures, they live at 110-120°c with a manual box. The engine coolant is below that, but there is 36~l of oil and 40~l of coolant in the system. And the clutch fan has an electric overide. Old mate needs to get over it, if he's the worried, change the engine oil more often in case of oil breakdown (modern oils breakdown around 130°c in testing however so just like the cooling system, not an issue. Interestingly in the 70s, Volvo cars supplied engine oil coolers with their r sport packages which amounted to increasing the compression ratio to close to 11:1 and a cam that was as hot as a GTR xu1 Torana. It is addition cooling but was offered worldwide not just in Australia.
exactly, drop a gear or 2 and get the revs up, get the fan and water pump spinning nice and fast and the turbo doing its magic rather than letting it pull right down in the revs under full load with the right pedal mashed
Great video John. One of your best recently. Interesting what you say about temperature loss across a turbocharger. Never really thought about that. Pertinent to me with a turbocharged Subaru EJ255 with TMIC weighing up a mod to a FMIC. We know it works but is it really worth it for standard power. (No). Best lesson I’ve had in ages thanks
He's talking about heat loss across the turbine side of the turbocharger (exhaust side). This work and the conductive nature of the turbo's components means that some of this heat loss is lost to the compressor side, heating up the aluminium cover and impeller, increasing your intake air temperature (IAT) under sustained load. Higher IAT reduces the effectiveness of the boost applied by the turbocharger and increases your exposure to the risk of pre-ignition when you're properly caning it. A bigger or more efficient charge air cooler and/or water sprayer (as JC says, water is a helluva heat remover/transferrer) is never a bad idea in Australia if you plan on taking the whip to your turbocharged car from time to time.
@@Low760 why turbo timers are a good idea. Cos switch off cooling stops but de heat in the blades goes into the shaft and then into the bearings drying out de grease Then your turbo goes sadly no more.
Many engines are designed to run at 215f (101c) or more. The cooling fans (electric) come on at 101c on every one of my GM vehicles from 1995-2010 by design. Boilover occurs at above 140c.
As touched on by some other commenters - what is the thermostat setting for each ute? My shitbox Navara climbs quickly to 95 and sits there +/-2 under most driving conditions. In the meantime, there's no movement on the temp gauge because the change is so small, even climbing to 105'ish towing uphill, still no movement...
Obviously: the ambient air temperature is also steady at just the right temperature to suck just the right amount of heat out of the coolant to maintain an equlibrium temperature... of 95 or thereabouts.... all things being equal, remaining the same and not changing in any way....
@@JohnSmith-yv6eq perfect point! I gave up using my OBD reader as I was having tech anxiety. Once that was gone, towing the shitour to Wolfe Creek and along the Gibb River was a way more relaxing trip... other than cows, boondies and invincible Landcruiser-drivers on the road. :P
Depending on the age of the vehicle, the gauge may not be a direct read from a sensor like in the old days. It may be passed through the ECM and displayed at the normal position for a specific temperature range.
Another thing that you didn't touch on, between the Hilux and the Triton, is the engine tune. Different AFRs and different boost levels at the "same" load will yield more / less heat being produced.
In my youth I drove a series of transports - motor cycles and a car - with air cooled two-stroke engines. These engines run hot because they're air cooled and the actual quantity of lubricant is quite limited yet they work well even under load and last quite well. Temperature is a relative thing, it depends what the manufacturer designed it for.
Well said about crash safety and bullbars at 7 minutes. I should also add: bullbars are lethal for anyone you hit, too - particularly pedestrians and cyclists.
Lower temps are the enemy. Pretty much everything I ever stripped was substantially more worn at the water pump end (colder) If the turbo doesn't split your oil, 125 C won't hurt it.
My first car had a gauge in that moved as you went up hills, had a tail wind etc, a few years later in a rental car I commented to a colleague that it was funny that the digital temperature gauge didn't move when going up and down hills yet my car did. The answer came back that my car was a pile of crap and his didn't move. Well I made comment to someone in the know and they said that the manufacturer's did it on purpose to give a guide as to when the car was warned up, they were fed up of customers complaining about the temperature reading not being in the usual place when towing, driving fast, going down long hills etc. Personally I would set the temperature ceiling to when the fan came on / turns to full, not when the coolant might boil as you can get localised boiling which can cause trouble. If in doubt you could probably find out when the manufacturer puts the warning light on and use that value. This reminds of an argument I had about why someone with a smaller car with a smaller engine could go just as fast as someone. He even had a chip, well the smaller car could also be chipped to the same level... duh it's a smaller engine, was all they could comprehend. I didn't realise that coolant helps your engine warm up faster, that's handy. BTW what's the temperature at which point the engine might start to fall apart, like by dropping valves etc? 🤓
I have the same heating issues with my Pajero Sport. I tow a 1.6 tonne van. I have put a really good aftermarket radiator in it and got it professionally installed. Hopefully that does the trick because I love the car in every other way!
So you don't have an actual problem then given 95°c is still below 120°c... Better to put in a colder thermostat or gear down so the fan will spin faster.
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Thanks for an excellent explanation of cooling and related issues in IC engines. I also fervently support you in your quest for improved understanding of scientific principles in the general population. I don't mean this in any condescending way. The scientific method is the only way by which understanding of the world around us can be gained. The quicker the education system is oriented towards this end, the better it will be, I hope! Anyhow, many thanks for an enjoyable discussion.
Dear John
Please share your feedback on the Ineos Grenadier.
How do I spell that word for trailer, the one that sounds like "shitwa"?
@@ldmtag Shittoir, similar to Pissoir. Shit*twa, Piss*wah.
These tutorials should be mandatory for schools, language may require a bit of editing for swears, would also be useful for remedial spelling and punctuation. 😆😂
One great thing owners can do is wash the rad. Quite a few years ago I was helping a mate move house up to the Kahncoben area in one of the hottest days of summer on record. His trucks temp rose to just outside the red zone, but not into it. It never missed a beat , and on the downhill it dropped back rapidly. He was concerned. As someone who has raced and rallied cars for a short time I wondered if the rad was plugged up from the outside. His hilux was immaculate but he had never hosed the rad and air con condenser . We soaked it when cool for about 10 mins then jet washed . An unbelievable amount of slurry and seeds and bits of bugs came out. The upshot was on another journey in the same heat the temp rose just a little and and the air con he said was better and the truck seemed quieter. Anyone remember locusts across Victoria and cars boiling at the roadside ?
Great tip, I agree. Another tip is to straighten any bent fins on the heat exchangers since they block airflow. There are "fin comb" tools available to make this easier, but a pocket screwdriver and some patience works great too.
I remember one trip down the Murray valley highway in summer 1975. You had to stop at every servo to hose out the locust slurry. The locals had rigged flyscreen across the grilles which sped up the cleaning process.
*Roadside BBQ locust sammiches?
Homemade French locust soup?
That sounded pretty scary. Any loss of traction, skidding, from all the locust goo on the pavement? During mayfly hatches in Wisconsin, many bridges are closed and have to be plowed and sanded come daylight because of the huge amount of dead mayflies. They also show up on weather radar. Outside in the streetlights, it looks like a snowstorm. 😲
Scientific literacy, convective cooling. You sir are a true fount of learning. This is the way our kids need to be taught at school.
I was only thinking that myself. I wish my science teacher when I was at school was as thorough explaining things as John is.
The way I learned the difference between heat and temperature is to picture two boxes in front of you, one containing air, and the other containing water. Both boxes are at 100 degrees Celsius. Now stick your hands into both boxes. The one with hot air will feel uncomfortable for a moment, while the one with water will scald you. They are both at the same temperature, but the box of water contains much more heat.
They didn't teach you very well.
@@mini696 What do you mean they didn't teach him well? Water has approximately 980 times more mass than air, therefore for the same volume of water and air at the same temperate, there is a factor of nearly 1000:1 difference in heat energy.
Remember, ignorance is bliss, right up until it isn't!
At the end of the process.
Edit. Dang, you just spilled the beans right after.
What differs is the amount of energy in them. Why do you feel a difference? Because different materials have different thermal conductivity properties.
And what also is part of this is that your skin evaporate water to cool it down in the air. Of course not possible in water.
There is heat transfer say KW/ m^2 with specific heat KJ/Kg x degree C.
My bull bar saved me last night. A roo jumped out last second on a single lane gravel road deep spoon drains both sides I was traveling at a safe speed nothing I could do.
Did it save your life or save you money? If you hit a pedestrian with that thing you'll see why we don't use them.
@@arcrides6841 saved me money saved any damage saved any chance of being stuck in the middle of nowhere with no phone reception.... so could say it potentially saved my life too. I will just also say that John saying you should drive better and not hit kangaroos should be doubled down and drive better and not have an accident as well lol
@@arcrides6841 also I'm not from a city nor do I travel to one in my ute there is reason I have a normal car for that there is a time place and reason for bullbars 👍
@@DTGTDetectingTheGoldenTriangle that does sound quite reasonable. Can't argue with that
Many yrs ago where I worked, we got new machines with Cummins engines. They were equipped with thermo fans that came on around 90 or 95c. The mechanics fitted override switches as in their opinion that was too hot. My opinion was I think the manufacturers know the range they want for operating temp!
But that one time crossing DP Creek towing max weight on a scorcher day....and the computer fan controller goes phutt.....
and the driver is awake and scanning his guages...
maybe..just maybe......
95C is too hot. 85C (185F) is ideal here in America while towing. You want some buffer in case you run into a situation with reduced air flow, like stop and go traffic
@@Noah_E considering that Cummins is American and they designed it to run at the temp.
@@Noah_E Did you listen to John's explanation? How is 95° too hot in a pressurised system where the coolant boiling point is 35°-40° hotter?
@@Noah_E : sorry Noah, did you watch all that - if~ 130C is the "upper range before some venting occurs.. 85 isn't even at coffee brewing temp, let alone approaching the danger zone... 125kpa (mine is 1445kPa 21 PSI)- over atmospheric / gague pressure...
Opinions don't matter in the face of evidence (the empirical knowledge base is extensive). -America Europe, Asia or Australia - facts remain.
This was well timed. I just did coolant service and out of curiosity I monitored my coolant temps via ODBII and got all these same consistent numbers so now I'm happy after watching this that my coolant system is running perfectly.
Geeze John, vehicle temperature gauges are very reliable and accurately tell you three things:
1. The engine is not up to operating temperature. Advice is don’t cane the engine during this time. The gauge reading rises during this phase
2. The engine is within it operating temporarily range. Typically 85 or 90 degrees through to around 115 or 120 degrees. No problem keeping your jandal down. The gauge reading is steady during this phase staying in the normal range
3. The engine coolant temperature is increasing above the normal range. The gauge reading starts to increase and moves into red. Advice is to back off the power.
Dingo Piss Creakians sometimes get to 3 early when they forget to remove the blind they put in front of the radiator before crossing DPC.
I do not have a temperature gauge in my car.
@@Xanthopteryx just the danger light when it's hit what would be the red zone if you had a gauge?
@@Wdeane1957 I really have no idea of what will trigger when, but there is no special light. you know, modern digital car (Volvo V90). So a message will show up telling me something, and the car will also adapt the system to not overheat, like restrict engine functions and similar. Sensors all over the place, and of course electric fan that goes on when needed and i guess they will automatically also restrict ac, maybe? Never had any issues, the system just works. Even when we had 30 degree C, full cargo and drove 470 km. No issue what so ever. Pros and cons of modern cars - the computers handles stuff for you. The bad side of it is that you have no idea of how it is programmed and what triggers when and how, and which parameters needs to be on a certain level and so on. The same for gearbox of course, and torque converter. It handles stuff by itself. And even when parked, if the car thinks it needs to cool down engine more, it will do that automatically. You stop, turn engine off, lock the car and sounds will still be heard under the hood. Electric water pump, electric shit everywhere. =)
Just unlocking the car and open the door makes a lot of funny strange noises appear under the hood.
@@Xanthopteryx 30°C is fairly mild here in Australia. I've driven through outback Queensland in 40-43° heat for 7-800 kms and thankfully my car (4WD loaded with camping gear) does have a temperature gauge, but for accuracy I also use a digital gauge that connects through the cars OBD2 port to monitor the precise temperature. I've seen 106° but that was up a hill and it soon got back to 86° downhill and less engine load.
@@Wdeane1957 I know, here in Sweden that is kind of hot, but instead we also have low temperatures. Record low in Sweden is -52,6 degree C and record high is +38 degree C. A normal year where i live can go from -20 (some times -25 and in a few occasions -30 C) and then +25 to +30 (some occasions up to 33-34 C). So in one year we can have 60-65 degree C difference.
That is also a struggle for the car, i can tell you. But, it just works. People here are towing caravans during high heat summer too. Older cars tends to sometimes get in trouble but modern cars with all their sensors alert in time and handles it better.
Interesting, perhaps Mr Triton should also consider the location of the temperature sensor on each engine and also the thermostat rating of each engine. The thermostat in the Hilux might simply open at a lower temperature where as the Triton might need a higher temperature to help with emissions. I have had 5 Land Cruisers over the last 40 years and they were all fitted with a bull bar and I have also done my fair share of remote camping trips. In all those years I have never hit a kangaroo so when we purchased a new Sahara in 2020 I didn’t get one fitted. My friends couldn’t understand why I feel I don’t need or want one. They always ask “but what if you hit a roo” and my answer is “that’s what insurance is for” I also add that I would feel a hell of a lot better hitting a roo without a bull bar fitted than hitting a child that runs out onto the road with one fitted. Something for the urban cowboys to think about. Cheers Stuart.
Maybe also the fluid mix. Did one have 70% ethyl glycol, while the other had 50%?
At TAFE we did a bit on Boyle's law, where it is stated that water boils at a higher temperature under pressure. This is the reason a vehicle's cooling system is under pressure from the radiator cap or on newer vehicles the recovery reservoir. When the drivers look at an analogue temperature gauge the centre part of the gauge is the most accurate.
Just putting this out there. Different engines will have coolant sensors in different places. Whilst it is possible that engine oil temperature (from directly inside the pan under the crank) may be a ‘more level’ playing field for comparing engine temps, it’s also well-known that different (types of) engines deliver their best power, efficiency and longevity whilst indicating different core and fluid temperatures at any 'simmilar' point of or between the sampled engines. The engineering and configuration is just different. An apple and a pear are sameish, but different, and both will sustain you.
@25:35, Spot on! There's a reason the factory (oil/coolant/AT fluid) heat exchanger is in the circuit. It’s to modulate the AT fluid temperature. Just like a coolant circuit thermostat, its job it to assist in keeping the fluid passing through it within optimal operational parameters. Thermostats and heat exchangers are there to facilitate both warming when needed, and cooling when needed. Modern ATs are very specific about the frictional qualities of their fluids and those fluids are only “in spec” when they are within the designed operating temperature range. Almost any AT on the road now will have a ‘brain’ and whilst it may compensate when its fluid is outside of its preferred temperature, it will not operate optimally until it reaches the correct temp range. You really always want that fluid up to temp ASAP and kept “in spec”. Interestingly there are ATF ‘cooler’ suppliers out there that state to bypass the factory heat exchanger. In my book, that’s just asking for trouble in cooler/cold operating conditions.
Thank you very much. I didn't want to get into this issue in that detail, because people are always telling me the reports are too long, but that's exactly what I was alluding to.
So ATF may be good for us regularly up north in Darwin, not so much in Gippsland, Victoria?
@@djjames6576
Look up de rale fluid thermostats that plumb into the auxilliary coolers of all types and fluids....
This is true, but the risk of failure and mixing is a seperate issue.
There are some cars where bypassing the standard cooler is a good idea if you don't want to be bringing all the boys to the yard (transmission) with the devil's milkshake. Think Falcons with a Barra and ZF auto. The standard cooler is so egregiously and atrociously flawed in its design that it overcools the transmission fluid, keeping it below temperature for twice the amount of time that ZF recommends and also likes to just split, without warning, introducing water to your auto. In this latter situation, the specific heat capacity of the water, while impressive, is unfortunately insufficient to prevent certain parts of the transmission melting and/or galling and welding themselves together.
Most kits that you can buy for these cars have a fluid thermostat and thermostatic fan switch, so they do more good than harm in most cases. You just have to use your brain when purchasing/fitting/talking to your mechanic.
FRICKEN AMAZING episode! I followed along perfectly and clearly the whole way through. The way you explain things is like my dad used too; solid facts, real life examples, direct. I really enjoyed this topic also as it is something i would think about it when driving through 40C !
I recently upgraded my v8 landrover motor from the 100hp military unit to the 180hp Stag motor one. A few years ago I rebuilt the military 2 row radiator to a 3 row core. Even driving "giving it the willies" in deep river run gravel in low ratio 4wd the radiator temp never goes over 90 deg. I run standard 50/50 coolant and I suspect that its still withing the proportional control of the 85 deg thermostat.
Good job explaining thermodynamics to your viewers. You did a fantastic job.
I spent the first 10 years of my career as the design engineer for a boiler making company, so I appreciate the effort you must have put in with these questions.
J.C . Excellent science engineering and maths with a humorous twist. Your best work is in that realm.
FYI, most manufacturers hold the temperature needle in the middle of the gage anywhere from 66 degrees to 100. The computer tells the needle where to go .
Thanks john for another great show digging deep down into the " TURD MINE".
The only thing that freaks me out when towing, is how much diesel I've just gone through!
Sorry mate but there is a cost to every thing … try a higher capacity Petrol Engine and you might be more pleased with your Diesel …
If I was towing in my car I would be worried as I don't have a towbar...😉
Only tow downhill and problem with diesel and temperature is solved.
Thanks for all your hard work bringing us content and trying to help people.
I have a 1999 AU Falcon and it was running 'cold' all year round, I changed the radiator cap 3 times and had very little difference in temp, I felt the optimum operating temp should be higher... so I replaced the thermostat again and sealed the unit and temp rose a couple of degrees, yay...up to proper temp.
In my 2016 BT50 the 'high speed' fan didn't cut in climbing a hill with AC at flat chat and 3 kids onboard and it went well into the red line and power dropped like a bride's nightie, needless to say we crawled up hill as I shut the AC off, wound down the windows and put the heater on flatout with the fan flat out and lo and behold the temp dropped power picked up, I did a U turn and rolled down the hill I was just climbing, all the power came back so I put the AC back on and took it steady driving home, 2 days later the Local mechanic replaced the clutched fan. No issues since.
So just a trick that's saved me a couple of times is to turn the inside heater fan on and flick the heater unit on to get the temp down fast!
Thanks John...
Great vid. The ultimate thing what I got out of it was ego, dude didnt want to slow down to lower his running temp.
Why slow down?
Drop down a cog and the engine viscous fan slould suck more air across the convective cooler...
or the electric fans should kick in if working properly....
Thanks. Great information for people who tow stuff
Brilliant sciencey stuff, I love the explanations and the DEPTH. I was getting a bit heated pulling myself and my 2.7ton van (3.0 Isuzu) while climbing the Clyde on Kings Hwy with my roo bar blocking my airflow. After watching this beautiful description with voiceovers I am heading out to drop my glycol ratio to increase heat transfer and remove a bash plate restricting air flow. Thanks for that mate, I also liked and subscribed! Love your work.
Hi John - Great video - as an engineer who has worked in heat transfer / thermal management for around 25 years, I feel that you have done a fantastic job of explaining the topic - a topic that most technical people struggle to get their heads around. In fact, I am considering getting my engineers to watch it as a training video…
Other things to consider with the 4x4 comparison:
1. The coolant temperature is often linked to the emission controls - ie combustion temperatures need to be controlled in a relatively narrow temperature range which means that coolant temperature (particularly around the head) can’t vary too much. (Many industrial engines de-rate engine output once the coolant temperature exceeds their maximum design point - for example 107 or 110C). Maximum operating temperatures vary from engine design to engine design.
2. Different engines have different coolant flow rates - this varies significantly from manufacturer to manufacturer and just measuring the coolant temperature can be misleading.
3. I might have missed it, but did you mention the thermostat? Many thermostats start to open around 90C - unless the thermostat is removed and the by-pass blocked, any coolant temperature measurement below at least 95C is probably not representative of full flow through the radiator.
4. Finally thermo-fan control also influences coolant temperature - fan control (along with the thermostat) is used to manage coolant temperature. Whenever the AC is operating, at least one thermo-fan is operating regardless of engine load / ambient temperature, and this further influences the coolant temperature.
Thanks Derek
I have a mr triton an just towed a 2.2 tonne caravan 7500 km and had no overheating problems.I tow at 80-90 km great vehicle happy as with it
Thanks
Good work John! Not a bad effort, yet again. There's one thing that would affect the operating temperature range very considerably between the two different vehicles, that I didn't notice you mentioning (sorry if I missed it because of the noise I had in the background while listening to your video). The thermostat.
The chance of the two test vehicles having thermostats with identical operating characteristics is virtually zero. For instance, the factors involved in thermostat design include (but aren't limited to) initial opening temperature, fully open temperature and flow area, whether there's a warm-up recirculation circuit (including initial and final closing temperatures and flow rates), radiator circulation bleed area (allows some flow through the radiator, even at low coolant temperature), linearity (or otherwise) of the flow area increase from closed to fully open, etc, all of which will considerably change the coolant temperature at any set of engine operating conditions.
Powertrain cooling systems have been one of my areas of particular experience while I was a warranty engineer (ie: finding and fixing the mistakes of other engineers after customers have experienced problems) for two OEMs. I can back up your assertion that the temperature gauge calibration is deliberately made to leave the needle in a position that won't potentially alarm the driver, as long as the engine's temperature is within acceptable limits. However, the gauge is also usually calibrated to frighten the brown stuff out of the driver if the temperature starts creeping up too high, so the driver will be more likely to pull over and let the engine cool down (after all, going outside acceptable limits is, by definition, unacceptable). My advice to the man with the question is to perform all due-diligence checks and maintenance per the book (if not, a little more often), and just drive the vehicle. It sounds like the temperature gauge is doing exactly what the manufacturer calibrated it to do.
From my point of view, as long as there are no coolant leaks, bulged or worn hoses, emulsified water/oil mixture, or white semi-powdery substance build-up at the ends of any of the coolant hoses (caused by weeping of the hoses and/or hose spigots), there probably isn't a lot to worry about. Bulges or wear in hoses can burst, leading to catastrophic engine/transmission failure, and the bulges are often, but not always, caused by electrochemical degradation of the rubber hoses. The white powdery stuff is an indication that there's either a hose that has a pin-hole into the webbing layer, or a plastic radiator end-tank hose spigot is deteriorating, and potentially about to dump the coolant (if the plastic has discoloured or started pitting, it's on its way out). Emulsified water and oil can be a multitude of expensive problems, including a leaking in-radiator transmission fluid cooler (requiring an absolute minimum of flushing of the transmission and engine, possibly also replacement of all coolant hoses due to chemical degradation from contact with the oil, and maybe even transmission replacement). Note that aftermarket transmission coolers might not have been adequately pressure fatigue tested (there are usually high-frequency pressure pulses in the system that many people don't know about - been there, seen dead transmission coolers before, especially in cheap knock-off radiators). Then there's good-old machining chips, that somehow haven't been removed from the engine's manufacturing processes, that can get stuck in radiator and heater core passages, fretting away until they wear holes in the tubes. Oh, what fun coolant systems can be when something goes wrong! 😉
Excellent reply, thank you!
One thing I have noticed when using a obd-II scanner is to take into consideration the "Coolant Temp Commanded" by the ecu as well as the "Coolant Temp" in addition to the "Current Oil Temp". New diesels tend to run hotter for greater efficiency and the engine oil needs to run (generally) at around 105-110ish to ensure that impurities such as water in the oil is dissipated out through the crank case vent. 100deg under load uphill is fine. Wonder what % the cooling fan is running at - I would lay odds its running at only 30-35%.
Another reason for the difference between the Hilux and the Triton. If the Hilux is substantially older - think pre-DPF - then its design operating temperature will probably be lower than a new engine designed for improved efficiency.
It's interesting to watch my Edge CTS3 telemetry screen.
With my 6.6 litre Duramax V8 diesel, one of the huge number of parameters I can choose to monitor is the cooling fan rpm.
This cooling fan looks like a typical viscous type. However, it has an electrical connection as well, and there appears to be a method by which the ECM can vary the rpm.
This can actually be done to the point where the fan rpm is higher than the crankshaft rpm. Go figure.
Most of the time, though, the fan rpm is very low.
@@billroach2393 as an Australian, it's fun to see fan speed reach 80-90%.
Great video John. I do love the grammar corrections too.
Two things come to my mind.
1. When measuring water temps it is important whether it's the temperature of the water leaving the engine respectively entering the radiator or leaving the radiator. I would consider 110°C leaving the engine perfectly fine but 110°C leaving the radiator rather hot.
2. Modern engines tend to run hotter for better efficiency. Some engines run at different temperatures in the cylinder head and in the bottom. Some other engines vary the temperature dependent on rpm and load.
Makes perfect sense to me , rule of thumb if it's not using water all is good, if the pressure cap releases generally you have big proplems
One of your best videos. Well, when it comes to something I'v been chasing for a while now in an older prado trying to keep it under 100deg calluses when towing thanks Jhon for great content very much appreciated...
Watch those calluses!
Have you ever taken the radiator to a good radiator shop and had them take the top and bottom tanks off and physically rodded out the tubes?
(Plastic top and bottom tanks alloy core)
If it's an all aluminium welded radiator it might be cheaper to replace the whole radiator as cutting into them if they are of all welded construction is not recommeneded.
Also is your fan a viscous coupling one as they can leak out the silicone thus reducing their efficiency by "slip" so not drawing ther needed volume of air through the radiator? (Toyota sells the silicone for you to put in the hub to restore it)
If electric fans...are you sure both fans work and are being "switched in" under load?
My turbo hatchback runs at 90C summer or winter, gains about 5C when you cane it, drops back down almost as quick when back at normal cruise. My previous car sat at 72C, so there's no "normal" temp for a particular type of vehicle.
Excellent explanation, as usual. I was ecstatic when you covered the difference in specific heat between water and a 'coolant' mix. But do you think old mate's going to get it, or is he perhaps going to suffer a cerebral haemorrhage trying? I certainly hope his personal cooling system is up to scratch too.
Read old mate's comment above.....😁
My old commodore ute would start to over heat towing my ski boat on a hot day. I'd get to an intersection halfway to the lake and then accelerate back to 100 and then watch the temp gage rise from half, to the red zone (if I didn't take action). So what I'd do was 1; AC off (temp would still climb) 2; window down. 3; heater and fan on full ! temp would drop back down to halfway on the gage. Amazing how much the heater core could contribute to the cooling of an engine that had a radiator blocked with bugs! I never did get around to cleaning the fins out on that one, but I made sure I put some fly wire in front of my current one.
Fly wire actually forms a barrier (quite a substantial one) to all airflow......
so you are reducing the cooling available to your radiator...
and probably more than say the effect of one month's worth of bugs.
As you indicated..
cleaning the radiator of bugs
say once a month
would keep the radiator airflow where it should be...
(I have seen those flyscreens or equivalent stainless steel mesh used where 4wd bush bashers were pushing through wild grass areas at seeding time for those plants....and they are definitely good for catching those seeds before they plug up the radiator fins in mere minutes!)
My 3 HJ's were the same. They were fine until they were under load, then the cooling system would show itself for all it was worth, not much. I miss Australian manufacturing, I don't miss what they manufactured.
@@JohnSmith-yv6eq yes the fly wire acts as a barrier, but it catches the bugs right at the front and allows much easier cleaning. I’ve never had to turn the ac off and heard on since 👍
@@davidbrayshaw3529 I was talking to a radiator shop about replacing a broken radiator with a fancy one. He said don’t bother. He’s never seen a Holden (later models at least) overheating that wasn’t because of a clogged up radiator.
Thats an old Rodders trick. So is fitting a windscreen washer setup to spray radiator . lots of ways to cheat teh system.
Thank you so much for doing this episode. This was so good to know as I do keep an eye on my temps when towing. Your explanation, including the glycol mix was great to learn. Excellent information explained in terms I can understand. Probably the most beneficial episode for me that I've watched.
ironman bullbar blocks the lower section of the airflow.
most modern diesels run at 90 deg and using a ob2 reader it will most likely read more than 1 temp reading and often not the one that is connected to the temp gauge.
the VW amarok has 3 temp sensors and the gauge will read 90 but the other 2 will read between 80-108 when working hard.
If you fit an extra probe to the top radiator it reads 90 so the gauge is the exit temp.
The cooling system is working as designed and different parts of the motor produce more heat than others like the block but once the coolant flows around and reaches the thermostat that only opens at a pre determined temp eg 90 deg
I feel the oil temp is a more important indicator on when you should drop back a gear and slow down once you get over 128 deg
coolant temp 110 deg slow down as well
I'll add two bits of info. A radiator cap doesn't control normal running system pressure. In a typical cooling system the designed running pressure would be about 6-8 psi. The cap would release at the rated pressure to release in the event of over pressure due to various not good scenarios. Also, too much ethylene glycol used as a coolant in concentrations over 70% will actually reduce the boiling point, go figure !
Cool video John enjoyed that one
Cool 😂
Learnt heaps today. More of these lectures please.
You remind me of some of the TAFE/course instructors I've had over the years . I'm in aviation engineering, and have always maintained my own vehicles . I enjoy your videos, and the wealth of information - keep it up.
hey John your vinegar vs rust tools works a treat thk you for the tip cheers bloke
Our Land Cruiser 200 will run at 85/86 all day on the HWY at 110km/hr,whether it is 5 degrees outside or 40degrees.Hills it may get up to a tops of 90 degrees which drops off very quickly once at the top.Towing,GCM of 5T,around 87/88 degrees at same speeds on HWY,max on a big hill i have ever seen it is 93 degrees.Auto fluid temps seem to rise about 8 to 10 degrees when towing.
Thanks muchly for the vid, very informative and useful for me as I have just started towing a 2.5T caravan and also recently acquired a ScanGuage. Having said that, whilst I love looking at all of the live data, I really don't know what they either mean or what is good and what is bad. With regards to my engine temps, I figured out that the ECT, (Engine Coolant Temp) has become my focal point while towing. Ironically, I too have a Triton (MQ), I find that my non-towing ECT sits around 85-90C, while towing, I have seen it max out at around 102C, which to be honest made me a little nervous. However, after listening to your explanation, I feel somewhat more comfortable that hitting the 100C or just above is well within what would be a reasonable temp threshold. Thanks again John.
Spot on with your comment about a turbo being a heat exchanger.
In a Nissan Patrol I used to own, I installed two thermocouples; one in the manifold and the other in the dump pipe.
Under full song, the temp difference between the two could be as high as 200 degrees C.
It is for this reason that I drilled and tapped a hole in one of my manifolds on the 6.6 litre Duramax V8 in my 2012 Silverado 3500 4x4.
Brilliant, makes me feel more relaxed about ‘normal” temperatures in a well maintained cooling system :-)
Another very informative video.
It is too true that most people have no idea about the sort of technical data they can access in everyday life.
I wish we could instill your teaching style in American education system. Outstanding!!!!!!!!!
Another really informative video, thanks John! I load up my Pajero Sport and go bush all the time. The temp gauge never moves above 'normal' but my scan gauge reads 100-120°C all day and night without any problems. I use the Mitsubishi coolant and replace it as per the maintenance schedule.
Once again ... BRILLIANT !!!
Thank you John. I’ve been concerned with my engine temps when off-roading often seeing 105d. Won’t worry now 😌
Great video John.
I've got a TD42 Patrol and have had the temperature guage on the "H" up a big hill fully loaded.
The Watchdog read 105°
I pulled over and everything was fine under the bonnet.
If anything it was running better at that temperature.
I wonder if that's why the Triton runs a bit hotter, to make it more fuel efficient?
In marine applications the units with header tank heat exchangers were always 2 to 5% more efficient on a grams per Hp hour rating. The ones that ran salt water with anode protection were 20% cheaper to buy but otherwise identical. Example Yanmar 3GM30 vs 3GM30F. The water jacket temperature difference was 60C vs 90C
All the TD diesel engines have a design fault where they run warm under load, the TD 42, the TD 27 that's why Nissan never released a turbo version for a long time, and when they finally did it was a low boost, and if you doubt me, ask someone who aftermarket boosted one and then used it hard what happened ( or google it), the head was simply not designed to disperse heat well.
All very interesting but you overlooked the importance of an EGT ( Truckers call it running on the Pyro) and there is a good reason. I cooked my Isuzu by pushing it too hard for too far up a long central north island main road. Very expensive . Had I fitted the EGT that I had sitting at home I would not have run the exhaust temperature high enough to overheat the oil and effectively turn it to water eg non lubricating super low viscosity overheated oil pumping around and not lubricating anything.
I recon that exhaust was running at >800C for >20minutes based on my subsequent use and observations from running the rebuilt Motor C/W EGT . where I run it at 350-550C for most driving and under 600C for long hill climbs and allowing a brief peak of 650/700 particularly when towing.
or as a 4x club member did . Drove home at motorway speeds not knowing his front locker was stuck on lock. the extra load from continuous wind up together with a long engine killer hill near home seized his engine and the front diff caught fire. (put out with a compulsory carried powder fire extinguisher (club rule) The rebuild engineer commented that the oil was as thin as water.
For both instances Interesting that when the engine seized the water temp gauge was right on the middle normal temp I assume around 88C.
My understanding is that modern common rail diesels will shut themselves down if the predetermined max oil temperature is reached then Enable a restart when the oil cools down. So fit an EGT or an oil temp gauge if you are pushing your wagon and want to know it.
Informative video once again from bogan beard striker. Few items with video.
1. Triton has the worst towing due to the position of rear wheels. Any load on tow bar lightens the steering. So your item of evasive driving isn’t as effective.
2. Mitsubishi sell bullbar as standard option when you purchase a new vehicle. If they effect the towing then they wouldn’t have them as an option.
3. Bullbar, maybe in your state Vic & NSW you don’t require them. Come over to WA & NT you may change your mind. Idea of bar is to protect the radiator & lights so in remote outback you can get home. A light alum bar is a good accessory, not the heavy cow scraper bars.
Keep the videos coming there good education for outback wonders.
Thank you John. I enjoy the scientific, systems thinking you provide in your videos.
Here are a couple comments for the discussion.
1. Based on your explanation, any difference in the ratio of water to coolant between the two vehicles will also contributed to the observed water temperature differences.
2. The process of planning trips to limit the amount of driving at dawn and dusk will reduce the risk of hitting a kangaroo by avoiding the times of greatest macropod activity, and therefore the probability of encountering Skippy altogether, before even needing to rely on your defensive driving ability.
Great video and really valid points, could it also be connected to the different thermostat specs ? Google suggests that Hilux opens at 82 and Triton at 91
Here in New Zealand it was inevitable on any hot sunny day during the holidays to see a Holden standing at the side of the road caravan in tow, wife and kids standing around and the man staring forlornly at the steam geyser issuing from the radiator neck after he had undone the cap because the car "overheated"....
GM was well known for only providing a radiator that ony just coped when brand new and the temperature was "average"......
But was the wife's name, Cindy?
I rem yrs ago when GMH changed the name of their Temp Gauge to Temp Indicator due to persistent complaints of overheats in the 6 cyl engines.
Great explanation John, very informative...
Spot on. I’d also add that it is likely that the modern Triton engine is working more efficiently (converting chemical energy to effective work in a smaller combustion space, with less surrounding radiative mass) ergo likely to be lifting the temperature of the combustion process and surroundings etc, than is the case for an older lazier Lolux. Similarly the design of the liquid-to-air (“radiator”) of the more modern Triton will be seeking to do more work (exchange of energy) with less metal, less circulating fluid, less mass overall and probably smaller radiator assuming all other things equal. That is the Triton is likely to have have a more efficient cooling system design from the perspective of mass etc, therefore will NEED to operate at a higher temperature than the Lolux. Adding an auxiliary cooler will undo aspects of design by adding mass, complexity and points of potential failure. I also dare say the manufacturer’s specification for lubricating oil in the case of the Triton and Lolux will match the design envelope of the operating temperatures. I suspect the oil spec of the Lolux would not meet the requirements of the Triton - no surprise. Going to your bullion robber analogy, the guy carrying 24 bars would be sweating like a pig, but still be the man to depend on.
Hey John , one for comments driven trucks for a few years 35 plus . CAT engines running temp 100 c , most EURO trucks 95 C so running at 95 should produce a more efficent combustion ? Great two videos ( sorry about spelling ) Cheers Chris
I had a problem where I couldnt go up a hill towing on a hot day without the coolant hitting 105 and my AC turning off. It was fixed by changing the viscous fan hub to an aftermarket tru flow hub. Did the same hill with the same trailer in same weather conditions and it didnt go above 90 degrees. The factory hub was designed for fuel efficiency and didn't kick in until 105. Not good when thats when the AC its turned off it stinky hot conditions. Id rather lose fuel efficiency for a cold AC and cool engine
It is why the Billy boils faster in the mountains.
And at a lower temperature...
See “Charles Darwin boiling potatoes in the Peuquenes”. The book is “Voyage of the Beagle”. The nearest high ranges are above 7500 feet which isn’t high but enough to mess with boiling a spud. He seemed a bit glum about boiling a potato for 24 hours only to have it as hard as it was when first put in the pot
Milk first tea or coffee. Agree with your point but in the example the hot water fucks the first milk added, but if you do hot into cold it tempers the milk better
When making tea, hot water has to go in first. lol.
Yes. Perfect explanation.
As long as the cooling medium is still present, there is no real problem.
Not sure where the coolant disappears to if you top up your expansion tank. My vehicle gives a level. If I fill to the level, a week later it’s just below the bottom indicator. It doesn’t go any lower between services. Should I not top up to recommend level?
The sh*... er coolant expands (shock horror!) as it heats up. Then, surprise, surprise, it shrinks when it cools down!
@@gregbailey45 Lol, thanks,
I just wonder why it always settles below the bottom level,
@@goldfools5445
It's just being a bitch...
or you have a small leak in the seam of your overflow tank (not under pressure?) at that level?
@@goldfools5445 do you top it up or check it cold or hot?
Probably leaking somewhere. Externally or internally 😢
Totally agree with your tutorial here. I wonder if you could do one on auto tranmission temperatures and at what temp is the auto about to have a problem.
125°c is when the oil is going to start breaking down in engine and transmission oil.
Synthetic trans fluid is good for 275°f (approximately 135°c) this is it's breakdown point where the fluid starts to degrade quickly and can cause damage. My truck's computer puts it into limp mode if the trans hits 265°f.(I've never seen it, that's just the manufacturer's settings) most I've ever seen was 115°c on a 30°c day pulling a 2.5t up a steep grade while merging with highway traffic.
Haven’t watched yet but my 2012 2.1L C250 diesel sits at about 90 degrees when warm. Just over half the gauge.
The hilux will be reading 3 to 5km lower than the speedometer is reading
This used to madden me as a mechanic. If the temp gauge is in the normal range, (barring some extremely unlikely specific fault) then the engine is operating at the correct temperature for that vehicle.
If it goes into the red or things start beeping or flashing at you, that's when you have problems.
My physics teacher at high school asked the same question as you regarding when to add the milk to the cup of tea. I always thought adding it later was the way to go. He actually said it made no difference!
Back in my auto instrument days we used to regularly recalibrate temp gauges for Mitsubishi dealers to make them read a tad lower. It solved a psychological problem for the owners who drove the service departments mad. The owners would not believe that their uses/vans were not overheating.
Hi John,
Great video, loaded with important fundamentals.
Although I wish to highlight that I have a different assessment of the "hard ceiling" of the temperature range.
The thermostat reads an average of the water temperature in the water jacket, not the maximum temperature adjacent to any hot spot in the head.
The hard ceiling is the temperature at the hot spot, not at the average temperature.
We need to have some buffer between the temperature reading and the boiling point of the coolant.
Should we rename the radiator to "convector"
It may take a while to catch on.
Cheers.
The coolant temp gauge has been irrelevant for years, probably decades for some manufacturers. It used to fluctuate according to the actual temperature and had the numbers of the readout printed on the instrument. With skills diminishing, cars becoming more precisely engineered and more of an appliance, manufacturers decided that instead of teaching drivers to monitor the instruments it was easier to make the needle stuck in the middle for the whole range of the normal operating temperature. Nowadays, the temp gauge does not exist in many cars and instead there is a blue light for cold coolant, blank for normal and red for high temp which I think is a better approach to the meaningless stuck in the middle gauge. Personally I think having a number of instruments to monitor, like generator output voltage, oil pressure and temperature, vacuum etc in a vintage car is part of the appeal. You are connected to the machine and operating it rather than sitting on a sofa with wheels and the computer telling you what you can and can’t do.
I do not have a gauge and no light either. Volvo V90.
And my oil stick is digital.
And if coolant level goes too low, it will tell me. If engine goes on too hot it will tell me and reduce power. If gear box goes too hot it will tell me and reduce power. I also have a coolant curtain(!) that opens and closes depending on some... factors. Makes for less drag when driving if it is closed. Keeps heat better in cold weather. And so on.
Thanks John I have learnt a lot from this video , I think my digger is getting hot because it has too much anti freeze in it . Cheers
Hi John, the supposed temperature difference between the hilux and trident could be as simple as the thermostat. In most cases they start to open at about 82 deg c, fully open at some higher temperature. They are relatively basic and it would not be surprising to find a 5 degree difference between two new ones let alone one new and one old at fully open. That is if they are in fact specified at the same temperature, which they often are not. Pop into supercheap for a look.
P's I apologies for my poor Grammer and punctuation in advance. Kiwi you know. :)
Top hose at 108C isn't the end of the world with a pressurized system. Get yourself a copy of thermodynamic & transport properties of fluids (it's a book) and see the effect pressure has on boiling point.
The hotter the coolant, the smaller the rad can be, with aero and pedestrian protection benefits.
Great explanation. They used to say "ignorance is bliss". It ain't anymore.
Very informative video John. I'm not a Triton fan personally, but thanks for the explanation.
Very informative, great topic.
Hi John, another thing to check is the routing of the transmission as mentioned by you. Climbing a hill will create heat in the oil and transfer some of that into the Coolant. My Pajero is a bastard for doing it. Regards
Hi John, technical description, TERRIFIC!
Expat Australian living in Phuket Thailand, ALWAYS watch your videos, feel free to visit us in Phuket.
Best Regards, M
once the air con stops blowing cold air its too hot, towing at a lower speed means your not labouring the motor
and CHANGE DOWN GEARS!
Have had an AU Falcon cut the aircon when I was towing at 80kmh.....
on a straight slightly sloping road...
and down in second gear already....
how slow do you want me to go...
Acording to my book on diesel engine design the problem with diesels is preventing over cooling as they tend to run too cool for optimum fuel efficiency and oil life.
I have a curtain in my Volvo. It is closed when engine is cold and opens if needed by engine or ac system. And it also makes the car get lower consumption since when closed there is less air resistance.
Pretty funny that curtains was on like all cars before, then removed, and now back again.
Just did 3,000km up and down the Great Dividing Range at 3 different locations between Qld border and Lithgow/ Katoomba, in a manual 2019 MR Trition towing 2.3t, seats full, 180kg ball download and 350kg in the tray. Had zero problems.
Sounds more like an engine understanding issue. Failing that it could be a user, gauge/sensor, thermodynamic understanding or a maintenance issue rather than a Mitsubishi design fault.
The MR Triton temp gauge reads in the middle from 70 to 110 degrees c. It goes up one square at 110.
John. Many thanks. So well explained.
Great explanation as usual, I agree about the safe temperature range. I do respectfully disagree about installing a transmission oil cooler before the heat exchanger in the radiator being superior for the reason you stated though. Every automatic transmission vehicle I have seen with a cooler integrated into the radiator was designed with the cooler in the COLD side of the radiator, which doesn't necessarily warm up very much or at all in cold weather. That's a very common misconception. If you feel the lower radiator hose after driving around town on a cold day, you will likely notice that it is actually cold! Every OEM cooler setup I have seen with a heat exchanger integrated into the radiator and an external cooler placed the external cooler after the radiator's cooler to return the coolest oil possible to the transmission. Manufacturers have recently started to use thermostats to block the flow through external coolers during warm up as well as oil to coolant heat exchangers fed by the hot, thermostatically controlled side of the cooling system to regulate the transmission's oil temperature, solve the problem of overcooling the transmission, and improve fuel efficiency and cold weather performance by getting the transmission warmed up faster.
Sir. You need to be a school teacher. You are an outstanding educator. Thanks!
My apprenticeship was spent chasing overheating buses and cooling them off etc. The dealer would have tested the coolant glycol %, and the fan. There's not much that can be done except fitting a colder thermostat.
Gearing down makes a huge difference on trucks when they have a weak clutch fan, on a hill at 60+ it will be getting into the actual red until it kicks down as well as the auto going over 130°c, despite that running a separate cooler and electric fan.
I've also watched the gauges on enough European trucks for oil temperatures, they live at 110-120°c with a manual box. The engine coolant is below that, but there is 36~l of oil and 40~l of coolant in the system. And the clutch fan has an electric overide.
Old mate needs to get over it, if he's the worried, change the engine oil more often in case of oil breakdown (modern oils breakdown around 130°c in testing however so just like the cooling system, not an issue.
Interestingly in the 70s, Volvo cars supplied engine oil coolers with their r sport packages which amounted to increasing the compression ratio to close to 11:1 and a cam that was as hot as a GTR xu1 Torana. It is addition cooling but was offered worldwide not just in Australia.
exactly, drop a gear or 2 and get the revs up, get the fan and water pump spinning nice and fast and the turbo doing its magic rather than letting it pull right down in the revs under full load with the right pedal mashed
Great subject Jack.
Great video John. One of your best recently. Interesting what you say about temperature loss across a turbocharger. Never really thought about that. Pertinent to me with a turbocharged Subaru EJ255 with TMIC weighing up a mod to a FMIC. We know it works but is it really worth it for standard power. (No). Best lesson I’ve had in ages thanks
You gain repeatable performance from a front mount intercooler, heat soak is a real thing.
Plus you also get heaps more street cred when you pull up with the boy racers. 😂😂
He's talking about heat loss across the turbine side of the turbocharger (exhaust side). This work and the conductive nature of the turbo's components means that some of this heat loss is lost to the compressor side, heating up the aluminium cover and impeller, increasing your intake air temperature (IAT) under sustained load. Higher IAT reduces the effectiveness of the boost applied by the turbocharger and increases your exposure to the risk of pre-ignition when you're properly caning it.
A bigger or more efficient charge air cooler and/or water sprayer (as JC says, water is a helluva heat remover/transferrer) is never a bad idea in Australia if you plan on taking the whip to your turbocharged car from time to time.
@@Low760 why turbo timers are a good idea. Cos switch off cooling stops but de heat in the blades goes into the shaft and then into the bearings drying out de grease Then your turbo goes sadly no more.
@@silkysixx Ah ok cheers for the deeper dive there.
I tend to keep a eye on transmission fluid temp when towing.
Loss of viscosity at high temps will grenade an transmission while towing.
My car takes care of all this. Telling me if something is not alright.
Plus that heat is being transferred to the engine coolant. If towing, run a good, well placed trans cooler,
Many engines are designed to run at 215f (101c) or more. The cooling fans (electric) come on at 101c on every one of my GM vehicles from 1995-2010 by design. Boilover occurs at above 140c.
As touched on by some other commenters - what is the thermostat setting for each ute? My shitbox Navara climbs quickly to 95 and sits there +/-2 under most driving conditions. In the meantime, there's no movement on the temp gauge because the change is so small, even climbing to 105'ish towing uphill, still no movement...
Obviously:
the ambient air temperature is also steady at just the right temperature to suck just the right amount of heat out of the coolant to maintain an equlibrium temperature...
of 95 or thereabouts....
all things being equal, remaining the same and not changing in any way....
@@JohnSmith-yv6eq perfect point! I gave up using my OBD reader as I was having tech anxiety. Once that was gone, towing the shitour to Wolfe Creek and along the Gibb River was a way more relaxing trip... other than cows, boondies and invincible Landcruiser-drivers on the road. :P
Depending on the age of the vehicle, the gauge may not be a direct read from a sensor like in the old days. It may be passed through the ECM and displayed at the normal position for a specific temperature range.
@@TonyRule Totally agree, but I would assume that what the gauge is getting from the ECM is the same as is getting passed to the ODB2 port
@@paulminchington6111 It may be. Then again, it may not be! Haha it depends on the philosophy the manufacturer happened to adopt.
Another thing that you didn't touch on, between the Hilux and the Triton, is the engine tune. Different AFRs and different boost levels at the "same" load will yield more / less heat being produced.
In my youth I drove a series of transports - motor cycles and a car - with air cooled two-stroke engines. These engines run hot because they're air cooled and the actual quantity of lubricant is quite limited yet they work well even under load and last quite well. Temperature is a relative thing, it depends what the manufacturer designed it for.
Well said about crash safety and bullbars at 7 minutes.
I should also add: bullbars are lethal for anyone you hit, too - particularly pedestrians and cyclists.
So is crossing the road staring at an iphone.
@@partymanau sure is. What’s your point?
Lower temps are the enemy. Pretty much everything I ever stripped was substantially more worn at the water pump end (colder)
If the turbo doesn't split your oil, 125 C won't hurt it.
My first car had a gauge in that moved as you went up hills, had a tail wind etc, a few years later in a rental car I commented to a colleague that it was funny that the digital temperature gauge didn't move when going up and down hills yet my car did. The answer came back that my car was a pile of crap and his didn't move.
Well I made comment to someone in the know and they said that the manufacturer's did it on purpose to give a guide as to when the car was warned up, they were fed up of customers complaining about the temperature reading not being in the usual place when towing, driving fast, going down long hills etc.
Personally I would set the temperature ceiling to when the fan came on / turns to full, not when the coolant might boil as you can get localised boiling which can cause trouble. If in doubt you could probably find out when the manufacturer puts the warning light on and use that value.
This reminds of an argument I had about why someone with a smaller car with a smaller engine could go just as fast as someone. He even had a chip, well the smaller car could also be chipped to the same level... duh it's a smaller engine, was all they could comprehend.
I didn't realise that coolant helps your engine warm up faster, that's handy. BTW what's the temperature at which point the engine might start to fall apart, like by dropping valves etc? 🤓
I have the same heating issues with my Pajero Sport. I tow a 1.6 tonne van. I have put a really good aftermarket radiator in it and got it professionally installed.
Hopefully that does the trick because I love the car in every other way!
So you don't have an actual problem then given 95°c is still below 120°c... Better to put in a colder thermostat or gear down so the fan will spin faster.
Any chance you can do a short video on how the thermostat works . What temp do they open and at what temp is it fully opened. Etc
Confess to considering an airbag compliant plastic bull bar for my Falcon but after seeing how much they cost, decided I didn't care that much.
You are roo ted either way.....