Brian, love you videos! This is the right way to check a thermostat. However I have to tell you that the spring is not Bi-Metal, it is just a spring. The capsule in the middle is filled with a fluid that expands and contracts at a certain temperature. This is what actuates the thermostat. The spring is what closes it. Keep up the good work!
One very important thing on a Subaru is to ALWAYS use an OEM thermostat when replacing it, the aftermarket ones are a different design and can cause elevated temperatures and other issues. Also, just to add, symptoms of head gasket failure on the older DOHC engines is bubbles in the coolant reservoir from combustion gases (you can also run air into the cylinder in a leak down to check for bubbles) as these ones had internal leaks. The newer SOHC engines had external leaks.
It's been a long time since you made this video so you probably already know what I'm fixing to say it's very simple to find out if you have a faulty thermostat in your Subaru 2.5 as you already know the thermostat is on the bottom of the engine .Start your car ,let it get hot, cut the car off, check your top radiator hose if it's hot check the bottom radiator hose it will be cold this shows that the water is not circulating and the thermostat is not working correctly.Also the little jiggle valve on the thermostat should be pointing at the radiator not the block. Thank you for your video
I have 2 Subaru Legacy's. Both have given me the same overheating problem at various times. The solution is ridiculously simple. Air gets trapped in the heater element, which sits under the dashboard and is higher than the radiator so that the air does not bleed out. There is no independent thermostat bypass in a Subaru. The hot water flowing through the heater element re-joins the main cooling system at the thermostat and acts as the thermostat bypass, heating up the thermostat so that it can open. The thermostat is at the bottom of the engine and receives cool water coming back from the radiator which causes it to close unless the bypass coming via the heater is flowing properly to keep the thermostat hot. So if you have an airlock in the heater element your car will overheat because the thermostat is not getting hot water to open it. This tends to occur more at low revs, like when driving in traffic. If you rev the engine this often pushes more coolant through the heater and opens the thermostat and suddenly the engine cools down again. The way to prove this is to bypass the heater element. Get or make a u-bend of 16mm metal pipe and disconnect the two heater hoses at the firewall behind the engine and join them together with the u-bend and two hose clamps. The overheating problem will go away for good. But of course, now you have no heater. The best solution if you want your heater to work is to cut both the heater hoses at a suitable spot next to each other and to fit a T-piece in each hose and join them together. (See photos). Then water can bypass the heater element keeping the thermostat functioning properly and enough hot water will still flow through the heater element to warm up the car's interior. This is the best solution, because every time you have work done on the cooling system, air gets in and it is almost impossible to get it out of the heater element again. You then get erratic overheating problems when you least expect them, and the symptoms mimic a blown head gasket, with water being blown out of the radiator and the expansion tank overflowing. Alternatively one can try to clear the airlock from the heater element by disconnecting the left heater hose and back flushing the element with a garden hose, then quickly reattaching the hose while trying not to let air in. But the above solution with the two T-pieces to bypass the heater element has worked better for me and provides a permanent solution, and getting air out of the cooling system after any future repairs will not be a problem again. I used a straight piece of hose to join across the T-pieces in the one car, and I used a U-shaped piece of hose in the other car. The U shape allows one to get away with not getting the T-pieces perfectly aligned, but can be hard to obtain. However a spare of the U-shaped rubber bypass hose that attaches the metal bypass hose to the thermostat housing is the right shape and diameter. see photos here: - www.cargurus.com/Cars/Discussion-t17159_ds614293
I bought my impreza with your configuration and thought that somebody in the workshop was falling asleep. I rejoined the hose as it were supposed to be and suddenly the car overheats like nobody's business. Now I understood why the coolant hose was bend and sent back to where it came from. Gosh, talk about poor design from Subaru...
I just jack the front of the car or put it oon car ramps. This way the the radiator cap will be higher than the heater exchanger thus allowing the air to escape. Good luck with the subarust.
Wow, I thought my 1999 Subaru Legacy was the only one who had that problem. No internet back then, no suggestions from mechanics either. It happened on a trip, the shop didn't have a thermostat available oh, so we just left it out. I forgot about that, drove another 60000 miles without one. Didn't have any problems at all. Heated well and cooled well. Crazy huh?
Man, you are a trooper! Thanks for the info. My car is overheating and I started to panic. Changed the oil (was well overdue), and found a loss of coolant. the only symptom that would match a blown head-gasket was the overheating. I figured that the Pressurized reservoir cap is a bust, or I accidentally introduced air in the coolant system the last time I saw it empty/ near empty, or there is a leaking hose somewhere I haven't seen yet. No visible leaks anywhere, and no coolant found during the oil change. I'm changing out the reservoir caps out for a new one. I'm also doing a super flush, and a proper burping, on the coolant system tomorrow morning. Wish me luck!
Hey man. Not sure when you will see this but I have an 02 subaru forester, just bought it a couple weeks ago. Its constantly overheating. Ive changed the thermostat twice an checked both of them an they both worked. Yes I burped it an made sure all bubbles were done coming out. But the subaru keeps over heating. I am unsure if its a blown head gasket or a bad water pump. I do not have any leaks or white smoke coming from the tail pipe or the engine bay. The car will run fine but if i drive it just down the road (5min or so) it will start to overheat again. When I just have the car sitting and running for 30min or more it's fine, it wont over heat at all. Just a bit perpexled. I've thought maybe its the radiator but it doesn't show any signs of damage or leaking either. I also took the thermostat off completely an hooked the hose back up an the freaking car will drive fine and wont over heat at all. So i'm assuming the water pump is fine also. Not sure how else to diagnose this issue to figure out what exactly is going on with the car. Would love to hear your thoughts on this. Thank you in advance!
Classic head gasket failure symptoms. Do a compression gasses test at the coolant tank while it's bubbling. If the fluid goes from blue to yellow it's a head gasket. The combustion gasses collect around the thermostat and it stays closed. you can drill four to six holes in the thermostat plate to let the gasses through for a temporary fix to get by.
Just got a 06 sti and it just temporarilly gets hot from 192-207. No leaking of rad fluid. Only when it's 100+ outside. Gonna try and "burp" and fill correctly, hardwire fans and then do the mishimoto therm and wrap my header... Dang corn fed big turboed subie. Thanks for showing me this
Brian, you are da bomb bro. Who knew that you could learn so much while being entertained at the same time? You are awesome. Even the simplest of devices are intriguing when you explain them. Peace brother!
Not sure if you realized just how much information,good and important information you actually spit in this video..ALOT. I literally took down some notes from things you said in this video..thank you.
I have this problem! I went ahead and replaced the T stat and it still boils into the overflow tank after 10 mins. Both top and lower hoses are hot and the bottom one seems to bulge a little. Trapped gases? Poor rad? 2005 outback. Great videos thanks!!
if took my 1995 subaru legacy to a garage,for overheating (temp gage goes to H after about 5-10 min + cold air only coming out of interior heater)can you tell me what I should expect for cost for replacement of thermastat vs head gasket failure. I really enjoyed your video as I know nothing about this and was able to get a fair idea how the heating system works. forgot to mention the interior air is quite cold-feels like a/c is on thank you
Hi thanks very much for this. I drilled a few holes in my thermostat flange and that really help. Car no longer overheat. Still have to check coolant daily to ensure coolant not get blown out too much from the system as the HG's still leaking.
Excellent advice. I'm a 74 year old senior citizen and I understood everything that you described and I can do this. Thank you bcuz I love my 2000 Outback AWS. I always view a TH-cam before I take it to the mechanic.😉
Very helpful video! I had my whole coolant system inspected and radiator replaced and still experiencing overheating. Thermostat is hopefully the cause!
The spring is made of spring steel and does not cause the thermostat to open, the capsule in the middle opens the thermostat. The other thing to check during an overheating event is a plugged heater core not flowing enough coolant to the thermostat.
I have a 2008 Subaru Forester Turbo, blue, tan leather interior. I know, awesome. I bought it with 50,000 miles on it, have had it for 3 years, put maybe 5,000 miles on it. It's my second Forester because the first one was awesome. 8 months ago, there was smoke coming out of the engine, coolant, overhearting, needle went red almost immediately, didn't even crawl up. Put in a new aftermarket radiator. Every two months it overheats out of nowhere. Dealers are stumped. Brainsmobile, prove yourself.
This was the most helpful video, explanation, possibilities I could find! Thank you so much. I learned a ton in just that small time frame. Things no one has informed me of in a month of trying to figure out wtf is wrong with my car.😊
On my mothers Forester she kept complaining she could smell somthing. And of course when I go over and look nothing. well after months of this, I was replacing a CV boot and saw a slight tell-tale sign of coolant ontop of the exaust right uncer the seam between the head and the block. Strange thing is there was no noticable loss in coolant. I guess on her long shopping excursions, it would heat and warp just slightly and allow coolant out-air in and form bubble on the termostat eventully.
Thermostats work via that little brass cylinder in the center , it's a "wax motor" , it contains a small brass pellet, as the temperature around it goes up, it expands, working like a hydraulic cylinder to move the valve against the spring. Cut an old one open and examine it. As far as "peak oil" goes, I've read articles from people in the petroleum industry that say over 90% of the oil is still in the earth.
I'm a VW Vanagon guy, the water cooled motors are notorious for bad head gaskets. A good tell is to hook a pressure gauge into the cooling system, with a bad gasket pressure will quickly (3 minutes) go to 15 lbs, normal is slowly (10 minutes) build to 7 lbs.. Might work for Subaru too.
It is funny you mention that. It is a TURBO and a couple of years ago, there was a long plastic thing that covered the bottom of the car that came loose. The mechanic took it all off and since then I have had this issue. He said it had something to do with air flow.
Hey Brian I'm currently working on my 2003 Subaru legacy wagon with an overheating problem. I've changed the radiator, coolant temp sensor,PCV valve ,and it still gets hot after 20 mins of driving. Do I change my thermostat next? Not a mechanic but learning fast because of your videos. Can't part with the car help
Worst case scenario: cracked cylinder wall on #4. Ever seen that before? Now I have. Thought it would be a standard head gasket job and then...GAME OVER lol
Test it while it's out. If it's good drill three small holes equally spaced in the main plate of the thermostat where the bleeder hole and brass bobble are.
Sounds like an 03-04 EJ25 (2.5L) These are VERY HARD TO BLEED AIR OUT OF. You have to "heat cycle" bleed them. Air collects and gets trapped at the thermostat spring. It takes a while to accumulate there, but when it does it shuts the heat off and begins to raise the temp quickly. The best thing to do is drill three holes evenly spaced like a Benz symbol in the plate just inside the O-ring and run it till the heat comes on- shut it down and let it cool. Come back and top off. Repeat.
My 2002 subaru legacy 2.5 began overheating a year ago.Did the head gaskets.Still overheating,at least the temp gaige says so.The mechanic says it's a faulty gauge and wants me to get another instrument cluster.I say,when he pulled the motor out,he didn't get all the air out and he put a thermostat in that is deliberately stuck open.I want to put the right thermostat in the right way but don't know how,and I'm done with that mechanic.Is there a certain position for the thermostat to be placed so air won't get trapped?
got a problem,i have a 2003 subaru outbback,replaced the head gaskets,thermostat,water pump,radiator,hoses,and it continues to over heat,the coolant builds up in resavoir tank and does not return to radiator.i am at my wits end,any suggestions (other than junk it as my friends say)
Brian , my 98 subi e20 would be dead without your , amazing ,guidance, it has 375 klm's , still going strong ,!st model of Forrester in Australia , Thanks my friend ,
Brian, How about leaving the factory thermostat out, and using an aftermarket inline hose thermostat, installed in the upper hose. Wouldn't that allow a good burp, eliminating the problem? Thanks for great videos. Example: JEGS 53260K1 In-Line Thermostat Housing Kit
If your head gasket is leaking and you've patched it up to make the car run without overheating as a short term fix by drilling the thermostat, you still have a compression loss that causes a weaker engine performance as a result.
I've been told that the combustion gas problem can be temporarily dealt with by drilling three small holes similar to the vent you showed because if that vent isn't sufficient or twisted to the wrong clock position gasses will still collect
My suburu is overheating after a few minutes of driving, i checked the therm and it works fine. Im not sure if it is a head gasket problem, because i figured if that were it it would have to burn off enough coolant to make it overheat, and it getting hot after just a couple miles when the radiator is full. So my question is do you think it could be a clogged up radiator?
This is very rare but I proved to myself that a free floating water pump impeller was causing the over-heating problem. Take out the thermostat, from under the car look at the impeller with a flashlight, try to spin the impeller with some type of prying tool. I was spinning the crankshaft while feeling the impeller movement. At first it seemed to be turning properly; but after a few tries it became obvious the impeller was free floating. That's tricky. After the pump is re[placed, I hope my engine will stay cool and the cabin heater will warm me.
Really appreciate this video and explaining done. My Tribeca keeps over heating we changed the radiator, fan and thermostat. But it keeps doing it. Last time we ran it without the Thermostat and it wasnt over heating. Is that a sign that its probably the head gaskets?
Hey Brian..my husband Barry commented about the Suburu thermostat and it saved us! I now would like to ask about the engine wants to stall when you have the air conditioning on and you come to a stop and, sometimes even when the air is not on the engine wants to miss at 40 to 50 miles per hour. Help, Sherri Hinkle
If your coolant is low, you need to find if you have a leak/ or if it's being pushed out by compression gasses. (head gasket failure). Once you top off the radiator the gurgling should desist. If it does come back you know you've got one of the for mentioned maladies.
I have a 97 legacy L wagon, and a few weeks ago I followed your channel because the car was overheating I replaced the thermostat. It's been running good since. Until today it overheated again so I popped the hood and there was no radiator cap, so I found and put it back on, but it kept overheating. I filled with water, and replaced the cap. It's not overheating, but the needle is just above the center mark on the meter. I am not a mechanic, and glad to have found you. What do you suggest is next for me to do with my car?
Usually that type of system is related to the ignition control module getting hot and there not being enough white heat conductive paste on it anymore so it burns up and cuts out when too much heat accumulates.
The right head was replaced 2000 miles ago with a felpro head gasket and a new head. Here we are again with the coolant pushing from radiator to the overflow tank. Do you think I'll have to have the head surfaced Or just replace the gasket? I've also heard to use 6 star head gaskets. Do you use these? I've heard they are very good.
Hey! I appreciate the video! I needed to know this! I got white smoke out of my hood. Never the back end. Now I am facing replacing an engine- even though I got it serviced before it blew. Keep posting! My suby is driving me nuts!!!
Nice review, Brian. It's worth emphasizing to your audience that every time an engine overheats, it runs a risk of causing expensive damage to the head and seals. Once steam forms within the water jacket, engine temp will skyrocket, pressures rise, and cooling capacity goes to ground. So, I wouldn't let a problem like this go for long without a diagnosis, or you could be facing secondary warping of the head, even if the initial cause was an easy fix.
Thank you so much for the video. Is there a video where you talk about the coolant pushing into the overflow tank and pushing out the tube that goes into the radiator neck? If there is not evidence of coolant in the oil, no leaks other than from the overflow tank and no some, what should I check? It is an 03 Outback with 260K, headgaskets were replaced at about 190K or so.
2011 Outback only overheats when the A/C is not in use, radiator, thermostat, and water pump have been replaced. Water pump was replaced for regular maintenance, the overheating issue started after the water pump was replaced 2 months ago. The thermostat and radiator was replaced to try and fix the issue. Suggestions ?
I changed out my thermostat and it seems like there in no fluid going into the line. My heat is not there and the outlet on top is hot. Do i have a clog somewhere? I did find cloth like material when i removed cap. Last owner used radiator stop leak I think?
@briansmobile1 You are freaking me out by your fast and nice responces..We have done everything that we can do. new raditor, new cap, new hoses so we know they are not closing up, checked on thermistat 3 times, checked the fan belts, the gear also and we made it spin faster, we had the entire top of the engine to make sure their was nothing stopped up. nowhere to go from here
Thank you, very comprehensive videos. I do have a Subaru, it have been good 2 me but lately I start 2 loose cooling, no white smoke, no green or humidity on oil cap, no oil deposit in the cooling idle thank, engine temperature indictor never show sign of overheat, engine sound good as usual. But My daughter borrowed it last wk and now sit on my driveway 4 overheat, I did change Thermostat but NO fix?????
I have another question. How hot is to hot. 1980 Trans Am after about 30 minutes of driving it reaches 214 degrees, its the original 301 non-turbo. thoughts? Love your channel..
Hi Brian. Thank you very much for these most helpful videos. You're awesome! I've never bothered to work on my cars in the past but am now learning to do a few minor jobs myself. You have a great way of explaining things. Your videos rock! Cheers :)
My gfs 03 legacy is over heating after about 10 mins or 30 mins of driving. Only one fan is kicking on. The driver side fan does not kick on. Both lines are hot.
Hi Brian. How about drilling an extra hole (or two) in the flange of the thermostat? I was having overheating problems before but now everything seems to be ok... The temp gauge stays level now. I'm just worried that if I do have a head gasket issue, all I have done so far is take care of a symptom instead of the problem. Is there any danger of my motor blowing up even if its not overheating? 98 Legacy GT ej25 Your videos are great btw! Thank you for all of the well-structured information!!!
You might mention that buying a aftermarket thermostat is not a good idea Subaru thermostat only also when it comes to the jiggle valve in my opinion it does need to be facing towards the front both of these things caused me a problem in overheating on my 97 legacy with a 2.2
Lots of great tips. I have one for you, check out "Uview Airlift" and you will never have a hard time getting all the air out,sure beats trying to use the bleeder valve. As for peak oil, syncrude up in Alberta has more oil reserves untouched than all the middle east. Great Vids Brian,well done!!
@briansmobile1 Its a new water heater, timing chain, motor oil after driving her for 2,000 miles look clean as it could be. new preasure cap on radiator too. Radiator is also new and does not leak. I am so lost..lol
Hi thanks for your videos, I just made a video of my 97' Outback having some cooling issues. Would you mind taking a look at it and giving me your input? I dont want to change the head gasket unless i really have to. Thanks again
@briansmobile1 Its basically an overhead cam version of the VW boxer engine On blown head gaskets/cracked head/cracked block - You forgot the 'mayonnaise' on the oil fill cap, and bubbles on your dipstick, along with an oil level that constantly goes up to the point it overflows out the dipstick tube
Air pockets in the engine going across the sensor can cause that. The sensor tells the temp of the coolant/engine where the sensor is. No more, no less.
Question: If I had a possible bad thermostat and had to drive about 300 miles to get home to change it, first, is that possible? If so, how would I do so safely without overheating or causing damage to my engine?
Awesome videos! So I have made my life extra challenging when taking off my thermostat housing, I broke off a bolt. It isn't flush with the block, but being that it is under the block I'm not sure any WD40 or PB blaster will get into the threads. Any ideas on how to get the bolt out or have I just killed made my car?
the thermostat housing bolts onto the water pump. The water pump bolts onto the engine block under the timing belt covers. At the very worst case scenario, you change the water pump. And while you're at it..change the timing belt and idlers ..they sell them in a kit that includes the water pump ..then you're good to go for another 100K miles..providing the head gaskets weren't the problem!
I let it cool down for like 20-30 mintues at a time and even tried using the heater to help it disipate heat. but once I got home, I stopped driving it and have a new radiator on order. I was just hoping I didn't kill the head gasket...it's my first and only car that I also plan on tuning into a racing car...
Is white smoke exhaust guaranteed to happen if a head gaskets blown on a Subaru? Is there a scenario a head gasket could be blown and you don't get white smoke?
I once had to temp cycle bleed one EIGHT TIMES before it would work properly. I cussed. Alot. That's 10min drive + 45min cool down times EIGHT. That's over seven hours! It's really stressful- especially when you've already covered your bases. There's an outside chance (8%) you have a cracked head and compression gasses are coming in, but you can test for that using a compression gasses test kit like in my videos.
Thanks Brian, once again you help us to remember the lil'things that sometimes in the complexidy of a job, we can forget or overlook these things. As far as the other topic. In my opinion(
Hey Brian, your videos are awesome! My 97 legacy GT is leaking oil right onto the cross member, I don't think it's my head gasket, any ideas? I hope it's not the rear main, or separator plate.
So I am thinking it is air in the system or may have faulty bad factory thermostat and leaning towards just replacing it and drilling an extra hole to bleed the air? I have checked for oil in the the radiator and did an extra oil change to check for antifreeze mixed in with the oil and it is all clear? I have Hayes manual and in the trouble shooting section they also indicate that it could be a bad water pump or a block radiator core. What are your thoughts on this?
Hi Brian, Can find this answer on google so Im hoping you can help. My 03 pathfinder overflows the overflow tank when Im towing a trailer with 2,500 pounds. I have towed 2k without a problem. I drive it daily with no issues. Cant figure it out! It is rated to tow 5k and the temperature needle is always reading normal. Any idea? Please?
Great videos! I've been trying to help a friend of mine with a forester a small dealer pawned off to him. Overheating ever since. I've personally never had one. Helped him flush fluids, change thermostat, etc. He has a family of 6 broke can't afford a mechanic so tried using liquid glass, head gasket sealer... I know, but just trying to get him by, 5 mile daily drives. Then I saw your videos. So I know it's temp fix as well but what size drill bit? and where should we drill? Thank you
"I'm at WKRP in Cincinnati" Thanks for the great video. What is the cost to replace the head gasket in this car if it had gone to the shop in your region?
Hi Brian, My subbie is acting up a bit, when cruising on the freeway temp goes up to 208 and hovers around 205. When car is not moving and idling goes to 205 and then fans kick in temp goes down. Lately tho, fan kicks in stays at 200, turn the heater on and temp drops slowly...... Could this be a sign of bad thermostat? Or is it head gasket? Thanks in advance
I've got a 2000 legacy outback, I've changed the thermostat, put new spark plugs, changed oil and filter, and top off engine coolant, and it's still over heating, It doesn't show any signs that the head gasket is bad but when I was putting coolant in it, the radiator kinda geysered. Heaters and defroster don't work so I think I need a new heater core but I don't think that has anything to do with the overheating. My engine fans work as well fyi. Anyone have any thoughts? Have not tried the burping thing yet, but will soon.
Brian, love you videos! This is the right way to check a thermostat. However I have to tell you that the spring is not Bi-Metal, it is just a spring. The capsule in the middle is filled with a fluid that expands and contracts at a certain temperature. This is what actuates the thermostat. The spring is what closes it. Keep up the good work!
One very important thing on a Subaru is to ALWAYS use an OEM thermostat when replacing it, the aftermarket ones are a different design and can cause elevated temperatures and other issues. Also, just to add, symptoms of head gasket failure on the older DOHC engines is bubbles in the coolant reservoir from combustion gases (you can also run air into the cylinder in a leak down to check for bubbles) as these ones had internal leaks. The newer SOHC engines had external leaks.
It's been a long time since you made this video so you probably already know what I'm fixing to say it's very simple to find out if you have a faulty thermostat in your Subaru 2.5 as you already know the thermostat is on the bottom of the engine .Start your car ,let it get hot, cut the car off, check your top radiator hose if it's hot check the bottom radiator hose it will be cold this shows that the water is not circulating and the thermostat is not working correctly.Also the little jiggle valve on the thermostat should be pointing at the radiator not the block. Thank you for your video
Wouldn't a dead water pump produce the same symptoms?
Ive had Subaru people tell me the bottom hose should be cool as the hot fluid is at the top coming in so it should be cool coming out.
I have 2 Subaru Legacy's. Both have given me the same overheating problem at various times. The solution is ridiculously simple. Air gets trapped in the heater element, which sits under the dashboard and is higher than the radiator so that the air does not bleed out. There is no independent thermostat bypass in a Subaru. The hot water flowing through the heater element re-joins the main cooling system at the thermostat and acts as the thermostat bypass, heating up the thermostat so that it can open. The thermostat is at the bottom of the engine and receives cool water coming back from the radiator which causes it to close unless the bypass coming via the heater is flowing properly to keep the thermostat hot. So if you have an airlock in the heater element your car will overheat because the thermostat is not getting hot water to open it. This tends to occur more at low revs, like when driving in traffic. If you rev the engine this often pushes more coolant through the heater and opens the thermostat and suddenly the engine cools down again.
The way to prove this is to bypass the heater element. Get or make a u-bend of 16mm metal pipe and disconnect the two heater hoses at the firewall behind the engine and join them together with the u-bend and two hose clamps. The overheating problem will go away for good. But of course, now you have no heater. The best solution if you want your heater to work is to cut both the heater hoses at a suitable spot next to each other and to fit a T-piece in each hose and join them together. (See photos). Then water can bypass the heater element keeping the thermostat functioning properly and enough hot water will still flow through the heater element to warm up the car's interior. This is the best solution, because every time you have work done on the cooling system, air gets in and it is almost impossible to get it out of the heater element again. You then get erratic overheating problems when you least expect them, and the symptoms mimic a blown head gasket, with water being blown out of the radiator and the expansion tank overflowing. Alternatively one can try to clear the airlock from the heater element by disconnecting the left heater hose and back flushing the element with a garden hose, then quickly reattaching the hose while trying not to let air in. But the above solution with the two T-pieces to bypass the heater element has worked better for me and provides a permanent solution, and getting air out of the cooling system after any future repairs will not be a problem
again.
I used a straight piece of hose to join across the T-pieces in the one car, and I used a U-shaped piece of hose in the other car. The U shape allows one to get away with not getting the T-pieces perfectly aligned, but can be hard to obtain. However a spare of the U-shaped rubber bypass hose that attaches the metal bypass hose to the thermostat housing is the right shape and diameter.
see photos here: - www.cargurus.com/Cars/Discussion-t17159_ds614293
I bought my impreza with your configuration and thought that somebody in the workshop was falling asleep. I rejoined the hose as it were supposed to be and suddenly the car overheats like nobody's business. Now I understood why the coolant hose was bend and sent back to where it came from. Gosh, talk about poor design from Subaru...
I just jack the front of the car or put it oon car ramps. This way the the radiator cap will be higher than the heater exchanger thus allowing the air to escape. Good luck with the subarust.
I'm having all the symptoms that you describe, than you for sharing!
Anthony van Tonder THANK YOU!
Wow, I thought my 1999 Subaru Legacy was the only one who had that problem. No internet back then, no suggestions from mechanics either. It happened on a trip, the shop didn't have a thermostat available oh, so we just left it out. I forgot about that, drove another 60000 miles without one. Didn't have any problems at all. Heated well and cooled well. Crazy huh?
This one helped me repair the grandson's wife Subi, head gasket malfunction. Thank you very much.
Man, you are a trooper!
Thanks for the info. My car is overheating and I started to panic. Changed the oil (was well overdue), and found a loss of coolant. the only symptom that would match a blown head-gasket was the overheating. I figured that the Pressurized reservoir cap is a bust, or I accidentally introduced air in the coolant system the last time I saw it empty/ near empty, or there is a leaking hose somewhere I haven't seen yet. No visible leaks anywhere, and no coolant found during the oil change. I'm changing out the reservoir caps out for a new one. I'm also doing a super flush, and a proper burping, on the coolant system tomorrow morning.
Wish me luck!
How'd it go?
Nice - in the last 5 minutes I learned more about cars than I have from all my time working on cars. Cool and thanks for the info.
Hey man. Not sure when you will see this but I have an 02 subaru forester, just bought it a couple weeks ago. Its constantly overheating. Ive changed the thermostat twice an checked both of them an they both worked. Yes I burped it an made sure all bubbles were done coming out. But the subaru keeps over heating. I am unsure if its a blown head gasket or a bad water pump. I do not have any leaks or white smoke coming from the tail pipe or the engine bay. The car will run fine but if i drive it just down the road (5min or so) it will start to overheat again. When I just have the car sitting and running for 30min or more it's fine, it wont over heat at all. Just a bit perpexled. I've thought maybe its the radiator but it doesn't show any signs of damage or leaking either. I also took the thermostat off completely an hooked the hose back up an the freaking car will drive fine and wont over heat at all. So i'm assuming the water pump is fine also. Not sure how else to diagnose this issue to figure out what exactly is going on with the car. Would love to hear your thoughts on this. Thank you in advance!
Classic head gasket failure symptoms. Do a compression gasses test at the coolant tank while it's bubbling. If the fluid goes from blue to yellow it's a head gasket. The combustion gasses collect around the thermostat and it stays closed. you can drill four to six holes in the thermostat plate to let the gasses through for a temporary fix to get by.
You are a good "explainer", Brian. Thanks.
Just got a 06 sti and it just temporarilly gets hot from 192-207. No leaking of rad fluid. Only when it's 100+ outside. Gonna try and "burp" and fill correctly, hardwire fans and then do the mishimoto therm and wrap my header... Dang corn fed big turboed subie. Thanks for showing me this
Brian, you are da bomb bro. Who knew that you could learn so much while being entertained at the same time? You are awesome. Even the simplest of devices are intriguing when you explain them. Peace brother!
Not sure if you realized just how much information,good and important information you actually spit in this video..ALOT. I literally took down some notes from things you said in this video..thank you.
I have this problem!
I went ahead and replaced the T stat and it still boils into the overflow tank after 10 mins. Both top and lower hoses are hot and the bottom one seems to bulge a little.
Trapped gases? Poor rad?
2005 outback.
Great videos thanks!!
if took my 1995 subaru legacy to a garage,for overheating (temp gage goes to H after about 5-10 min + cold air only coming out of interior heater)can you tell me what I should expect for cost for replacement of thermastat vs head gasket failure. I really enjoyed your video as I know nothing about this and was able to get a fair idea how the heating system works.
forgot to mention the interior air is quite cold-feels like a/c is on
thank you
@odewepe 195-198 is PERFECT! At 220 F gaskets and seals start going melt face.
Hi thanks very much for this. I drilled a few holes in my thermostat flange and that really help. Car no longer overheat. Still have to check coolant daily to ensure coolant not get blown out too much from the system as the HG's still leaking.
Excellent advice. I'm a 74 year old senior citizen and I understood everything that you described and I can do this. Thank you bcuz I love my 2000 Outback AWS. I always view a TH-cam before I take it to the mechanic.😉
Very helpful video! I had my whole coolant system inspected and radiator replaced and still experiencing overheating. Thermostat is hopefully the cause!
The spring is made of spring steel and does not cause the thermostat to open, the capsule in the middle opens the thermostat. The other thing to check during an overheating event is a plugged heater core not flowing enough coolant to the thermostat.
Thank you Brian for posting on youtube, your advice saved me from buying an engine. Thank you,thank you, thank you!
I have a 2008 Subaru Forester Turbo, blue, tan leather interior. I know, awesome. I bought it with 50,000 miles on it, have had it for 3 years, put maybe 5,000 miles on it. It's my second Forester because the first one was awesome. 8 months ago, there was smoke coming out of the engine, coolant, overhearting, needle went red almost immediately, didn't even crawl up. Put in a new aftermarket radiator. Every two months it overheats out of nowhere. Dealers are stumped. Brainsmobile, prove yourself.
This was the most helpful video, explanation, possibilities I could find! Thank you so much. I learned a ton in just that small time frame. Things no one has informed me of in a month of trying to figure out wtf is wrong with my car.😊
On my mothers Forester she kept complaining she could smell somthing. And of course when I go over and look nothing. well after months of this, I was replacing a CV boot and saw a slight tell-tale sign of coolant ontop of the exaust right uncer the seam between the head and the block. Strange thing is there was no noticable loss in coolant. I guess on her long shopping excursions, it would heat and warp just slightly and allow coolant out-air in and form bubble on the termostat eventully.
Thermostats work via that little brass cylinder in the center , it's a "wax motor" , it contains a small brass pellet, as the temperature around it goes up, it expands, working like a hydraulic cylinder to move the valve against the spring. Cut an old one open and examine it. As far as "peak oil" goes, I've read articles from people in the petroleum industry that say over 90% of the oil is still in the earth.
12 years into the future, we still working on the patents to batteries.
thanks for the info~!
I'm a VW Vanagon guy, the water cooled motors are notorious for bad head gaskets. A good tell is to hook a pressure gauge into the cooling system, with a bad gasket pressure will quickly (3 minutes) go to 15 lbs, normal is slowly (10 minutes) build to 7 lbs.. Might work for Subaru too.
It is funny you mention that. It is a TURBO and a couple of years ago, there was a long plastic thing that covered the bottom of the car that came loose. The mechanic took it all off and since then I have had this issue. He said it had something to do with air flow.
Hey Brian I'm currently working on my 2003 Subaru legacy wagon with an overheating problem. I've changed the radiator, coolant temp sensor,PCV valve ,and it still gets hot after 20 mins of driving. Do I change my thermostat next? Not a mechanic but learning fast because of your videos. Can't part with the car help
Worst case scenario: cracked cylinder wall on #4. Ever seen that before? Now I have. Thought it would be a standard head gasket job and then...GAME OVER lol
Did it leak coolant when your cylinder cracked? My 06 wrx just started leaking coolant from under the engine
Test it while it's out. If it's good drill three small holes equally spaced in the main plate of the thermostat where the bleeder hole and brass bobble are.
Sounds like an 03-04 EJ25 (2.5L) These are VERY HARD TO BLEED AIR OUT OF. You have to "heat cycle" bleed them. Air collects and gets trapped at the thermostat spring. It takes a while to accumulate there, but when it does it shuts the heat off and begins to raise the temp quickly. The best thing to do is drill three holes evenly spaced like a Benz symbol in the plate just inside the O-ring and run it till the heat comes on- shut it down and let it cool. Come back and top off. Repeat.
Can you help me? Sounds like the exact problems I'm having
My 2002 subaru legacy 2.5 began overheating a year ago.Did the head gaskets.Still overheating,at least the temp gaige says so.The mechanic says it's a faulty gauge and wants me to get another instrument cluster.I say,when he pulled the motor out,he didn't get all the air out and he put a thermostat in that is deliberately stuck open.I want to put the right thermostat in the right way but don't know how,and I'm done with that mechanic.Is there a certain position for the thermostat to be placed so air won't get trapped?
got a problem,i have a 2003 subaru outbback,replaced the head gaskets,thermostat,water pump,radiator,hoses,and it continues to over heat,the coolant builds up in resavoir tank and does not return to radiator.i am at my wits end,any suggestions (other than junk it as my friends say)
Brian , my 98 subi e20 would be dead without your , amazing ,guidance, it has 375 klm's , still going strong ,!st model of Forrester in Australia , Thanks my friend ,
Brian, How about leaving the factory thermostat out, and using an aftermarket inline hose thermostat, installed in the upper hose. Wouldn't that allow a good burp, eliminating the problem? Thanks for great videos. Example: JEGS 53260K1 In-Line Thermostat Housing Kit
Trapped air in the system around the thermostat. Drill a couple holes for burping. This WILL make your heater warm up slower, but not by much.
If your head gasket is leaking and you've patched it up to make the car run without overheating as a short term fix by drilling the thermostat, you still have a compression loss that causes a weaker engine performance as a result.
I've been told that the combustion gas problem can be temporarily dealt with by drilling three small holes similar to the vent you showed because if that vent isn't sufficient or twisted to the wrong clock position gasses will still collect
My suburu is overheating after a few minutes of driving, i checked the therm and it works fine. Im not sure if it is a head gasket problem, because i figured if that were it it would have to burn off enough coolant to make it overheat, and it getting hot after just a couple miles when the radiator is full. So my question is do you think it could be a clogged up radiator?
This is very rare but I proved to myself that a free floating water pump impeller was causing the over-heating problem. Take out the thermostat, from under the car look at the impeller with a flashlight, try to spin the impeller with some type of prying tool. I was spinning the crankshaft while feeling the impeller movement. At first it seemed to be turning properly; but after a few tries it became obvious the impeller was free floating. That's tricky. After the pump is re[placed, I hope my engine will stay cool and the cabin heater will warm me.
Having overheating of 08 legacy white smoke when first starts up it really Sims like thermostat I'll give it a shot
Really appreciate this video and explaining done. My Tribeca keeps over heating we changed the radiator, fan and thermostat. But it keeps doing it. Last time we ran it without the Thermostat and it wasnt over heating. Is that a sign that its probably the head gaskets?
Love the music in the intro i hope you don’t get copyrighted
Hey Brian..my husband Barry commented about the Suburu thermostat and it saved us! I now would like to ask about the engine wants to stall when you have the air conditioning on and you come to a stop and, sometimes even when the air is not on the engine wants to miss at 40 to 50 miles per hour. Help, Sherri Hinkle
If your coolant is low, you need to find if you have a leak/ or if it's being pushed out by compression gasses. (head gasket failure). Once you top off the radiator the gurgling should desist. If it does come back you know you've got one of the for mentioned maladies.
I have a 97 legacy L wagon, and a few weeks ago I followed your channel because the car was overheating I replaced the thermostat. It's been running good since. Until today it overheated again so I popped the hood and there was no radiator cap, so I found and put it back on, but it kept overheating. I filled with water, and replaced the cap. It's not overheating, but the needle is just above the center mark on the meter.
I am not a mechanic, and glad to have found you.
What do you suggest is next for me to do with my car?
dude your a genius and help me out more then you know thanks bro
Usually that type of system is related to the ignition control module getting hot and there not being enough white heat conductive paste on it anymore so it burns up and cuts out when too much heat accumulates.
The right head was replaced 2000 miles ago with a felpro head gasket and a new head. Here we are again with the coolant pushing from radiator to the overflow tank. Do you think I'll have to have the head surfaced Or just replace the gasket? I've also heard to use 6 star head gaskets. Do you use these? I've heard they are very good.
Hey! I appreciate the video! I needed to know this! I got white smoke out of my hood. Never the back end. Now I am facing replacing an engine- even though I got it serviced before it blew. Keep posting! My suby is driving me nuts!!!
That's air trapped in the heater core due to the coolant (antifreeze) being low in the radiator (as apposed to the coolant over flow tank).
Nice review, Brian. It's worth emphasizing to your audience that every time an engine overheats, it runs a risk of causing expensive damage to the head and seals. Once steam forms within the water jacket, engine temp will skyrocket, pressures rise, and cooling capacity goes to ground. So, I wouldn't let a problem like this go for long without a diagnosis, or you could be facing secondary warping of the head, even if the initial cause was an easy fix.
Thank you so much for the video. Is there a video where you talk about the coolant pushing into the overflow tank and pushing out the tube that goes into the radiator neck? If there is not evidence of coolant in the oil, no leaks other than from the overflow tank and no some, what should I check? It is an 03 Outback with 260K, headgaskets were replaced at about 190K or so.
+Platinum Distributing NE having the same problem with my 02 wrx. Hoping to get an update.
I have the same problem with my 2010 outback. Replaced the radiator, thermostat, and water pump. Still overheating after 12 miles of driving.
No. That would make the engine not ever warm up properly. The check engine light CEL would come on and the vehicle would not be as efficient.
@odewepe Is the water pump impeller rusted away? If not it's time for a compression gasses check at the radiator filler neck.
This is the best video I’ve seen, thanks for your help and information. Made perfect sense.
2011 Outback only overheats when the A/C is not in use, radiator, thermostat, and water pump have been replaced. Water pump was replaced for regular maintenance, the overheating issue started after the water pump was replaced 2 months ago. The thermostat and radiator was replaced to try and fix the issue. Suggestions ?
I changed out my thermostat and it seems like there in no fluid going into the line. My heat is not there and the outlet on top is hot. Do i have a clog somewhere? I did find cloth like material when i removed cap. Last owner used radiator stop leak I think?
@briansmobile1 You are freaking me out by your fast and nice responces..We have done everything that we can do. new raditor, new cap, new hoses so we know they are not closing up, checked on thermistat 3 times, checked the fan belts, the gear also and we made it spin faster, we had the entire top of the engine to make sure their was nothing stopped up. nowhere to go from here
Thank you, very comprehensive videos. I do have a Subaru, it have been good 2 me but lately I start 2 loose cooling, no white smoke, no green or humidity on oil cap, no oil deposit in the cooling idle thank, engine temperature indictor never show sign of overheat, engine sound good as usual. But My daughter borrowed it last wk and now sit on my driveway 4 overheat, I did change Thermostat but NO fix?????
Dis you find out what was the problem ?
@easydoz1 Keep an eye on that. If a fan dies and stops it can do that and then free up again.
Sweeeeet freestyle to the WKRP vocal melody!
I have another question. How hot is to hot. 1980 Trans Am after about 30 minutes of driving it reaches 214 degrees, its the original 301 non-turbo. thoughts? Love your channel..
Depends on how long you let it cool down. You can drive up to 5minutes when the engine is cold in most cars with no coolant at all and be OK.
Hi Brian. Thank you very much for these most helpful videos. You're awesome! I've never bothered to work on my cars in the past but am now learning to do a few minor jobs myself. You have a great way of explaining things. Your videos rock! Cheers :)
Saved me once again! your videos do nothing but help! Thank you!
My gfs 03 legacy is over heating after about 10 mins or 30 mins of driving. Only one fan is kicking on. The driver side fan does not kick on.
Both lines are hot.
Many good tips here. I'm new to the Subaru "boxer" engine. Thanks for the post.
Hi Brian. How about drilling an extra hole (or two) in the flange of the thermostat? I was having overheating problems before but now everything seems to be ok... The temp gauge stays level now. I'm just worried that if I do have a head gasket issue, all I have done so far is take care of a symptom instead of the problem. Is there any danger of my motor blowing up even if its not overheating? 98 Legacy GT ej25
Your videos are great btw! Thank you for all of the well-structured information!!!
You might mention that buying a aftermarket thermostat is not a good idea Subaru thermostat only also when it comes to the jiggle valve in my opinion it does need to be facing towards the front both of these things caused me a problem in overheating on my 97 legacy with a 2.2
Lots of great tips. I have one for you, check out "Uview Airlift" and you will never have a hard time getting all the air out,sure beats trying to use the bleeder valve. As for peak oil,
syncrude up in Alberta has more oil reserves untouched than all the middle east. Great Vids Brian,well done!!
Cooling a boxer engine isn't easy. Oil cooling could be improved with some air fins on the oil cooler and some directed forced air.
Brian would u recommend removing the thermostat and not replace it to prevent future headgastket issue?
I have a 2005 legacy non turbo and I love it.
It’s funny when you said people are cooking a turkey around this time. Im watching this on 11/26/20 😂😂 happy thanks giving!!
Brian , Have you ever used black pepper to solve a head gasket issue ?
@briansmobile1 Its a new water heater, timing chain, motor oil after driving her for 2,000 miles look clean as it could be. new preasure cap on radiator too. Radiator is also new and does not leak. I am so lost..lol
Hi thanks for your videos, I just made a video of my 97' Outback having some cooling issues. Would you mind taking a look at it and giving me your input? I dont want to change the head gasket unless i really have to. Thanks again
@briansmobile1 Its basically an overhead cam version of the VW boxer engine
On blown head gaskets/cracked head/cracked block - You forgot the 'mayonnaise' on the oil fill cap, and bubbles on your dipstick, along with an oil level that constantly goes up to the point it overflows out the dipstick tube
Air pockets in the engine going across the sensor can cause that. The sensor tells the temp of the coolant/engine where the sensor is. No more, no less.
@odewepe How is the radiator on it? Is it full of cat hair, corrosion, stop leak?
Okay, check the thermostat (pretty positive I have a head gasket leak,) first, thanks!
Question: If I had a possible bad thermostat and had to drive about 300 miles to get home to change it, first, is that possible? If so, how would I do so safely without overheating or causing damage to my engine?
Just wanted to thank you for your video, & helping me out !
Awesome videos! So I have made my life extra challenging when taking off my thermostat housing, I broke off a bolt. It isn't flush with the block, but being that it is under the block I'm not sure any WD40 or PB blaster will get into the threads. Any ideas on how to get the bolt out or have I just killed made my car?
the thermostat housing bolts onto the water pump. The water pump bolts onto the engine block under the timing belt covers. At the very worst case scenario, you change the water pump. And while you're at it..change the timing belt and idlers ..they sell them in a kit that includes the water pump ..then you're good to go for another 100K miles..providing the head gaskets weren't the problem!
I let it cool down for like 20-30 mintues at a time and even tried using the heater to help it disipate heat. but once I got home, I stopped driving it and have a new radiator on order. I was just hoping I didn't kill the head gasket...it's my first and only car that I also plan on tuning into a racing car...
The good old piston #4 problem.. its the way subaru designed the flow of the coolant thru the water jackets.. kinda like the human centerpeed..
Could be the knock sensor if it's a pigtail connector and it's on the drivers side.
Is white smoke exhaust guaranteed to happen if a head gaskets blown on a Subaru? Is there a scenario a head gasket could be blown and you don't get white smoke?
I once had to temp cycle bleed one EIGHT TIMES before it would work properly. I cussed. Alot. That's 10min drive + 45min cool down times EIGHT. That's over seven hours! It's really stressful- especially when you've already covered your bases. There's an outside chance (8%) you have a cracked head and compression gasses are coming in, but you can test for that using a compression gasses test kit like in my videos.
Thanks Brian, once again you help us to remember the lil'things that sometimes in the complexidy of a job, we can forget or overlook these things. As far as the other topic. In my opinion(
Hey Brian, your videos are awesome! My 97 legacy GT is leaking oil right onto the cross member, I don't think it's my head gasket, any ideas? I hope it's not the rear main, or separator plate.
So I am thinking it is air in the system or may have faulty bad factory thermostat and leaning towards just replacing it and drilling an extra hole to bleed the air?
I have checked for oil in the the radiator and did an extra oil change to check for antifreeze mixed in with the oil and it is all clear?
I have Hayes manual and in the trouble shooting section they also indicate that it could be a bad water pump or a block radiator core. What are your thoughts on this?
Hi Brian, Can find this answer on google so Im hoping you can help. My 03 pathfinder overflows the overflow tank when Im towing a trailer with 2,500 pounds. I have towed 2k without a problem. I drive it daily with no issues. Cant figure it out! It is rated to tow 5k and the temperature needle is always reading normal. Any idea? Please?
Great videos! I've been trying to help a friend of mine with a forester a small dealer pawned off to him. Overheating ever since. I've personally never had one. Helped him flush fluids, change thermostat, etc. He has a family of 6 broke can't afford a mechanic so tried using liquid glass, head gasket sealer... I know, but just trying to get him by, 5 mile daily drives. Then I saw your videos. So I know it's temp fix as well but what size drill bit? and where should we drill? Thank you
"I'm at WKRP in Cincinnati"
Thanks for the great video. What is the cost to replace the head gasket in this car if it had gone to the shop in your region?
@odewepe "water heater?" Any who. If the water Pump is good it may be a head gasket. Are both hoses hot?
Hi Brian,
My subbie is acting up a bit, when cruising on the freeway temp goes up to 208 and hovers around 205.
When car is not moving and idling goes to 205 and then fans kick in temp goes down.
Lately tho, fan kicks in stays at 200, turn the heater on and temp drops slowly...... Could this be a sign of bad thermostat? Or is it head gasket?
Thanks in advance
I've got a 2000 legacy outback,
I've changed the thermostat, put new spark plugs, changed oil and filter, and top off engine coolant, and it's still over heating, It doesn't show any signs that the head gasket is bad but when I was putting coolant in it, the radiator kinda geysered. Heaters and defroster don't work so I think I need a new heater core but I don't think that has anything to do with the overheating. My engine fans work as well fyi. Anyone have any thoughts? Have not tried the burping thing yet, but will soon.
Another sign of a blown head gasket is that if the white smoke coming out of the tail pipe smells like a fog machine.