How To Troubleshoot Cat Fuel Systems and Test Diesel Engine Fuel Pressure.
ฝัง
- เผยแพร่เมื่อ 30 ก.ค. 2024
- If a Cat Diesel Engine doesn't have good fuel pressure it can cause a lot of performance related issues. This video goes over the proper component identification and troubleshooting for most Cat Diesel Engines. Please leave questions in the comments section.
Did this video help you save time or money? @AdeptApe on Venmo or AdeptApe@yahoo.com on PayPal for donations, thank you so much for supporting the channel!
Great material, thanks. This helped me diagnose a Check Engine Light- code 94 / “limp home” mode activation on an ‘06 C7 in a motorhome. I replaced the fuel pressure regulator and it resolved the issue. Interestingly, it also corrected a light torque load 25-35 mph surge/shuffle condition that the motorhome had since I purchased it about 30K miles ago.
This fellow is real good... with good intentions... I am learning a lot with gratitude!..
I love your videos!!! I have a pre acert c-15. I started as a company driver on a Volvo 10 speed then got stuck in several automatics for a couple of years... finally bought a real truck lol W900. I bought it from the original owner (‘03). I have a mechanical background but I’ve never tackled anything like this before. I appreciate your logic. I’ve talked to mechanics who just like to throw parts at it. Ughhhh. Thank you for sharing your wisdom and knowledge!!!!
Thanks for the videos. They are extremely helpful for do-it-yourselfers such as myself.
when gears in transfer pump are worn or bone dry it can't pull a vacuum. We used to pressurize the fuel tank about 5psi or less and push the fuel up.
Check valves also leak back to tank . I just fixed a Mack 300 it was the check valve in pump on that motor. Excellent work thanks!
Great videos buddy, I love watching them. We don't do extremely ridiculous repairs where I work, but at least now when driver ask about the system or have in depth trouble shooting questions I can tell them something besides 'I'm not sure' and I will definitely refer people who have questions to your videos. Keep them coming bud!
+Mitch S Thank you for referring people and watching them. I've got a video about injector cups coming out next so stay tuned.
I have a fuel equalizing issue almost a 100 gallons. I've changed the feed 😂return l8nes and splitter value. Help
Man, I can't thank this guy enough.
cool. I am up in Buffalo N.Y. I watch alot of your videos over and over so I don't miss anything.
Do you work at a truck shop or are you an owner operator?
I don't have time or $ to go to school. All I basically can do now is watch your videos.
+Steven McHenry They're free at least and you'll probably learn slightly more than watching prank compilations.
I had a problem with secondary fuel filter swelling up because of over pressure on a 3116. Ended being a small piece of shrink wrap stuck in return line from someone not removing the plastic around filter properly.
What a great job you are doing specially for bigner
I appreciate all the knowledge sir, you're are truly helpful and I thank you for sharing your acquired know how🙌
I have question I changed my transfer pump regulator fuel lines to and from exam did pressure test with valve covers off to see if a leaking o ring at base at idle sounds great when put under load at fuel throttle it hesitant and acts if it's a air bubble then at test drive it gets on high side and acts if I'm running out of fuel please help
I have a problem on my HEP12725 3126 cat. Heui pump went out so we replaced it as well as a transfer pump (ford part). Everything seemed to work great for a week or so. Than a small fuel leak was discovered (plastic hose that connects heui pump and water separator) that we are replacing right now. Than I could not start the truck in the morning. Unscrewed fuel filter and it was empty. Filled it up and started the engine using starting fluid. Truck ran for 10-20 miles and stopped again. Same process to start. I am hoping that replacing leaking hose and fuel separator will eliminate the problem but if not, what are my next steps? How do I troubleshoot my fuel system? Thanks a lot
Hi, question?, you have talked about the C7 or 3126 fuel regulator at the back of the head. Information says it has an orifice that regulates fuel pressure based on a certain amount of flow and that it has a 5 psi back pressure check valve.
Is there a way to test this back pressure function? And its hold function? I have seen a number of comments about it being an occasional problem but no clear way to trouble shoot. Or do you just throw one in and hope for the best? I am in Canada and it is a 340$ item at the Cat dealer or perhaps you know another source?
Thanks, Bob
Thanks Josh. Great video! Very informative and complete. 👍😎
Very helpful info.
Quick question I have a noise coming from the secondary fuel housing . Kinda like a sound of a bearing going out . Gould that be the pressure regular value?
Thank for the video. I will like to now at hawmany milles do I have to change oil to engine cartepillar 3126
That is a really nice video bro you explain basically everything my question to you is I have had a couple of c15 they come here for service and they have the 0749 which is a secondary filter put in the primary putting them like that because client ask and they won’t start
@Adept Ape Hi, I’m having issues with my cat 320d 6.4 acert engine. The code is low fuel pressure on rail. The machine is still working perfect if you keep the engine speed dial on 8 or under. If you select 9 or 10 the engine enter on safe mode and loose power after a couple of minutes. Now It is doing on 8 too and I’m working the machine on 7 but it’s very slow.
I have replaced:
Fuel return valve (fuel rail)
Low pressure pump
2 Inyectors (they had little return)
Flush all fuel lines and filter base.
Any idea if what could be happen?
A lot of people say may be the high pressure pump but it is the only thing I didn’t change. I think the pump is very expensive for keep “guessing” the issue.
All this parts where diagnosed and replaced by a cat technician
Great videos and information thanks for sharing your knowledge.
Great video . I’m having a hard time finding that fuel tester adapter . Can you provide a link would love to buy one .
So you can change a low preasure fuel pump on a 3126 cat. with out pulling the huei ? Or do you pull the spring and plunger out and rebuild? THis huei has the oil resavoir.
Driving a C15 that has had filters changed recently but has high restriction on guage in dash and seems low on power. What do you suggest? Partial plug before transfer pump?
So I have a c15 acert converted to single turbo. Last week in the morning it fired up and almost immediately shut down. I tried priming it but the plunger was hard as a rock. After a long crank like 20 or 30 second it started to light smoking and stinking of raw unburnt diesel. Then it cleared up and ran weak so I changed both filters. Every morning it's hard starting like I described above but runs flawless after it starts. Where would you start
got a 3406e runs fine, but fuel pressure goes to zero almost immediately when truck is shut off any ideas? 85 psi when running.
I have 1998 fl70 glow plug / wire light on starts hard at high idle once hits 120 degrees or step on brake goes to low idle then back up and down !maybe sensor?
Great video, thank you. I do have a question on my C15. I have noticed the last couple of times I have changed the primary filthe fuel level is about an inch down in the filter. It used to be plum full. And now my truck does have a slight stutter. When you've got a higher demand for fuel. In a heavy pull, what could be causing that? I have tested pressure I'm around 95 psi at 1500 rpm. Thank you for any advice
Where can I get these fuel pressure testers please and thank you I’ve had a truck come in with fuel issues and couldn’t figure it out and would like more videos on fuel issues please thanks and thanks in advance for anyone’s help on finding fuel pressure testers for cat and other Diesel engines
is pressure supposed to leakdown istantly like it did after you stopped trying to start the one with bad ecm? My c12 does that but i dont have any starting problems and i have good pressure. I have new filter base and pressure regulator with no leaks. Just curious becuase i read that the engine is supposed to maintain the psi after shutoff
Can you make a video of all of your fuel/oil pressure gauges you use for diag? These are the best videos
C15 6nz.
I have the problem of straight engine oil coming out of my fuel return line. Thinking it could be cracked head.
It came in, had head gasket blown and #5&6 liner cracked. Replaced 5&6 pistons and liners new head gasket kit and spacer plate. Went to start fuel going in to front of head and only oil coming out of fuel return line.
Great info thank you for your knowledge!!
Hi I have a 2001 Thomas flat nose bus with a cat 3126 I have changed the fuel filter three times in a day because it keeps busting and releasing diesel. Can you tell me what may be the problem? Where is the heui valve is also?
i have problrm with 3126 no power... fuel presure is good 80 psi ,boost up to 23 psi ,no smoke,start well,no check engine what can i check , TANK
Hello. I enjoy your videos! Thank you! A question if I may...
I have a 04 C8500 with a C7. There are no trouble codes. I have an extended crank situation. I've burnt up or broke starters from excessive cranking. Once it does start my running pressure at the filter is 70 psi and the pressure immediately drops off to 0 when I shut the engine off. My cranking pressure comes up very slow. Attempts to start slowly at around 50psi. I've replaced the fuel regulator and the Injection pressure sensor. Thanks for your time!
Hi thanks for all the great videos! I am having an issue with fuel pressure in my cat c7. When the engine is running it seems to have good fuel pressure (I don't have gauges to test actual psi) but right after engine shutdown I lose all pressure. And the engine can't start. What would be the common cause of this?
Question. I have c15 with primary and secondary fuel system but would like to make it with a glass bowl system with one fuel filter. I've seen one on TH-cam and the thing I can't figure out where or how to buy is on the secondary they use a dummy filter 🤔. Obviously the primarily is changed to the glass bowl type filter and on the primary is left alone nothing is removed.
I have a c12 that keeps losing prime. Replaced the relief valve and the hand primer. Do you have any recommendations for next steps on the dish?
Very good informational video!
Awesome job again thanks mate !
adept ape, I need help bad! i got a 2000 3406e on a freightliner. Truck was missing pretty bad around 1500 rpms, we ran an injector test and found out injector 4 was missing.
we put a six pack,new cam,rollers,lifter bushings and new turbo. Truck runs great idling and you can stand on peddle when it’s parked and it sounds great. the moment you start driving it and it starts boosting truck runs like crap. almost like it’s chocking on boost. fuel gauge shows 90 psi on fuel pressure. told mechanic that was kinda low he said they forced more pressure in system and does same thing. i’ve been down for 3 weeks and don’t know where to turn. Thanks
I have a C7in my Sterling dump truck. It currently has a little inline primary fuel filter. Is it possible to add a bigger canister filter like the one you exampled in this video?
hello sir, is it okey to run the cat diesel engine 3412 for almost 5days of continues operation? I have a trouble on fuel pressure dropd from 60 psi down t0 25psi..
I have learned alot from your videos.
That's why I make them, glad you enjoy them. I keep getting more subscribers and videos so I keep making the videos.
You should have more likes buddy. GOOD JOB !
In your opinion would an in tank fuel pump be better like thats in gas systems? It would eliminate the vaccuum portion of the diagram.
thanks for this video!! was pulling my hair out changed all the tank lines and found out from here it was pressure regulator,,,,5 minutes
Im new to this diesel motors but we have a 94 peterbilt dump truck that has c12 and its not getting fuel so im replacing the transfer pump any tips on what else it might be thanks.
Hey I have 2004 international truck C15 Motor, I am having issues that it turnsoff anytime and then after that if I keep on trying it’s starts after 30-40 mins then go off again and I changed its batteries now motor crank but still won’t start any guess what going with it
Studying for upcoming remote diesel fuel systems class for my associates degree . getting started earlt
Sorry just saw your message. I work full time for the city of buffalo as a mechanic at the highway garage. Then I work part time for johns towing out of Tonawanda ny. Towing and doing road service. Also help out at Beaumans garage in Lockport by basically doing the same thing and doing in shop repairs on cars, light truck's and rigs.
Only three jobs! Such laziness would not be tolerated here, just kidding.
Well done sir!
Adept Ape i have i 2004 GMC C7500 as you know it has the 3126. Do you have any video about replacing fuel level senor?
My 3116 boggs down and acts like it’s starving for fuel. Changed the filters and it ran strong again for a couple of days and now it’s slowly starting to do the same thing. If I pump the primer pump a few times it’ll run strong for about 20-30 minutes then it’s back to losing power. Where the throttle linkage on top the pump it’s seems to be slightly wet. Any ideas where to begin, could it be the fuel pressure regulator? Thanks
Hey Adept Ape. My 2010 C13 is getting 4.3mpg trying to figure what could be wrong
I have a 3406e that will not fire. I think it lost prime. Changing the prime pump today, it may have been letting air in.
Amazing videos! Best / Top information ever! Thank you!
Hi- can you maybe help me? I changed the separ and the yellow cat filter and the regulator vent on the handpump- everything was fine for 8hours driving and then i have again after starting fuel pressure alarm. I can override it with gas in neutral- then iam back on 520kpa- but what should i do next to prevent problems?🙏🏼🙏🏼
my engine when cold idles really rough ,and smoke out the stacks, replaced all 6 injectors , smoke disappears when hot ,idles rough still, but every once in while the engines smooths out and runs so good it is scary ,lots of power ,really works well, then for no reason runs rough again , could it be one of the reman injectors are bad ,injector driver module,fuel injection control module ,,,,I'm lost ,can't figure it out ,I will put it back on computer again to do cut out test,,,any suggestions ,,
Love your videos! How stable should the fuel pressure be on a 3116? Needle flutters quite a bit(centered around 10 PSI) at idle, occasionally dips from 60 to 35-40 then returns, when running at higher RPM?
Sounds like your sucking air. Fuel gauge is going to flutter a little bit but that big of a jump is air
I am having starting problems with a 3208 CAT, starting with easy start but not on it's own, trying to find glow plugs or heating element but can't see them anywhere, DOES IT HAVE THEM ?
I have a 3126 Caterpillar motor and once I start up rolling and I'm losing power after the 7th Gear the RPM is high then it's starting to flutter choke on me so what could be the problem after this I shut the engine power off and let it cool off a little bit for 5 minutes then it takes off again
I would love to know what kind of sight glasses yall use to check for air in fuel. Any part numbers would be appreciated
Hi man,how about the low pressure in my engine CAT C32 acert,i have some problem if rpm up to 1080 my fuel pressure is different with other engine.my first engine when i'm push throttle until rpm 1400 the fuel pressure is look good in monitor by 520 kpa.BUT when i pull my other engine until rpm 1080 the pressure is 484 kpa and when i try to up the rpm of engine,the fuel pressure is not stable still in range of 404-484 kpa.and when i pull all my engine into rpm 1430 my right engine is fine with pressure but my trouble engine can reach that,but the alarm is on to make the engine shutoff and pressure is drop until 320 kpa.can you tell me whats wrong man with my engine?thank you :)
Hello, what causes a diesel engine not to start unless you start it with ether. It will run fine and start. But if it sets over night you have to hit it with ether. It is a cat engine in a dump truck not sure of the size I thought I heard my son say it was a 331? Maybe be in the 1990s ? He's had several people tell him what the problem might be and he's replaced different parts that were suggested could be the problem. But no change. Still hooked on ether. Any advice. Thanks
I have a 2001 year model 3126B and after setting over a couple of days it is hard to start, when it starts it skips and misses for a 5 or 10 minutes then it runs ok continually and ok when you cut it off and on (we deliver stuff and start and stop a lot) What could that be?
Great video! Appreciate it man.
Hi, your videos are great, perhaps you could help me with a problem I`m having the problem is we have a 2008 Ford F650 rollback back wrecker with the Cat. C7 I first noticed the fuel primer pump was extended whenever I checked the oil so I replaced it with another one from Caterpillar. Yesterday the pump knob and stem blew off along the road and left me sitting I towed it back and replaced it again. The question I have is this a symptom of another problem or just a coincidence or do I have something going on? If you could help me, it would be greatly appreciated.
Thank you in advance. Don
Have a problem with a cat c-15 accert (accert disabled). New rebuilt engine. New cat injectors. New head. Always has a starve for fuel issue at 1600 rpm. Everyone says to install a FASS pump. I think that is BSZ Where can I get proper fuel line sight glasses for this diagnostic application? What else is needed? Where to buy? I wanna see the in and out of fuel and see if I see air bubbles! Damnit. Could it be a bad fuel filter housing? Check ball? Is there a screen somewhere? Has a new fuel pump as well. Thanks!!!
Hello sir i need your help i have a cat 312d if i switch the hydraulic activation control liver the engine is straggling almost knocking
hello I have a cat 3126 I seem to be losing fuel pressure I can get the truck to start if I pump it with the hand pump it will run for a few and turn right back of I changed the fuel transfer pump on the back of the heui same thing the question I have is can a bad injector o ring cause me to lose fuel pressure
Impactful. Thank u
Hi
caterpillar 3306 generator set
The diesel engine is unresponsive when running
Your opinion
What is the problem
please reply
Hi, I have a cat c15. It takes long crank in the morning. I'm assuming it needs check valve. Can you tell me where is the inlet check valve. Thanks
Very good video... thank U
Great video! I have a 2000 3116 that wont start, it has a hand pump on top of the secondary filter..... so somewhere between it and the fuel pump will be a transfer pump?? And being a smaller cat 50 to 60 psi cranking is ok for fuel pressure
+zeke1eod The 3116 is a little different than the other Cat engines in that if I remember correctly the fuel actually feeds the back of the head and then comes out the front. There is a fuel transfer pump, but it is a small one more similar to an automotive fuel transfer pump on a carbureted engine. That fuel pressure seems high, I would have to check, but I think the 3116 only ran with like 30 psi of fuel pressure.
So Adept Ape i have talked to you once before about my 3126 in my 2002 GMC rollback. So recently i have developed a miss at idle and under acceleration. It has gotten so bad that it takes forever to get up to highway speeds. I went to my local truck repair shop that had the proper computer to talk to my truck. He did a cutout test and at the time the injectors showed no issues and all passed fine but it was just at idle. That weekend i changed both fuel filters, Oil filter, and oil, also did a transmission service and replaced both batteries. Also did a valve cover gasket to get rid of some oil leaks. Checked the injector connections at that time and did not see anything out of the norm. put everything together and the miss is still there.and it gets worse when it gets warmer. There is no fuel or oil in the coolant and there is no oil in the fuel tanks. i did a little research and read about changing the fuel pressure regulator. Changed it with a CAT part and no luck it is still missing. So im at a lost as to what it could be it has no issues with starting it just has the miss please help with anything i could check. I thought about pulling the injectors and checking the O-rings. Or i thought it might be the HEUI pump or the fuel pump on the back. I have the tools to work on this, it is just im 30 years auto tech not diesel. So any help or direction to start will help because having a tow company time is money Thanks again and keep doing the videos I m on the west coast so im the same time as you.
+Steve Porter You should send me an email it is much better than this comment system for discussion when we go back and forth. AdeptApe@yahoo.com So an intermittent miss with no codes. First thing you need to do before trying figure out what it is, out a mechanical fuel pressure gauge on that engine and then route it so you can see it while you drive it. What is the fuel pressure reading while the engine is missing? First thing to check I would say.
Excellent video sir.
Hello,we have a cat C9 on Claas combine and we have sometimes low fuel filter pressure.When we dismount the fuel filter we see that filter is dirty and have Brown colour.Can we have some engine oïl going to the fuel return and then to the filter.thanks
+Jp S If you have a HEUI C9 it is very possible you have an injector or injector seal leaking HEUI oil into the fuel system.
I was thinking this after reviewing some CAT schematics.thanks a lot for your all work and videos.Regards from France
Rate your channel bro keep up the work ...... For the big engines you can bypass the primary filter..
hi, the problem of my generator is when start the generator the rpm is normal 18001 and the hz is 60.0 but if i put load the generator rpm will go down 17998 and also the hz go down 50.8 until the generator going to shutdown automatically,can you help me pls.. my generator is catterpillar 700kva
Got one where the hand primer keeps breaking popping out as if it’s building too much pressure what could be the cause?
GOOD I REALLY LIKED IT
Hello! Enjoy watching your videos! I have a problem with my cat c15, is acting like when you have a bad diesel filter which I already change and still doing the same thing, I change the turbo sensor and the diesel pump, diesel pressure valve and no luck. I had two mechanics look at it and they say everything looks good and no check engine light. Can you help me out with a clue please
Hi morning. Does a bad fuel pressure regulator cause lost of engine power? I have a cat 3126 with very low power..
I have twin marine 3126 420hp engines. Recently I noticed higher fuel consumption (12.5% more) on the STBD engine coincidental with loss of WOT power/RPM's at 2500 in stead of 2800. No oil consumption. I run 40wt oil.
I got a cat c7 engine and am in need of simple tips to remove the fuel pressure regulator from the back of the head please sir
Hi there , good job
I love watching your videos! They are so educational and helpful. I’ve learned so much. I have a question about this. I have a Kenworth T800 with a c-13, I started losing power in a stuttering sort of way like fuel filter was clogging up. So I changed out the filter and now it is worse. I can barely move in a parking lot. Worst part is I’m in Kremmling Colorado and there’s no mechanic. I called around and they all say that all they would do is change out the fuel filter. So I’m stuck with no help. Any suggestions on what it could be? Or what I could do myself to maybe get closer to a shop?
What was the problem? I’ve got a 3306 doing the same thing I cleaned the tanks out changed the filters and replaced the fuel lines it’s still doing same thing
I've had 3 fuel primer pumps go out on 3 different trucks truck was sucking to much air at the primer pump to start im assuming seals inside the pump go out truck cranks and cranks won't build fuel pressure pulled the primer pump off made a block of plate to go where the primer pump was truck starts right up
It even informative than some of the institutions
good day adept ape. you got some really good videos, learning a lot. my name is noel. I'm a licensed on highway heavy duty, hear in Calgary. I have a question for you. I am working on my brothers 2003 GMC Top kick T6500 with a CAT 3126 in her. now my question is, for say 10 min driving down the road, it running great, than it looses throttle response, starts to run rough and white smoke, pull off the road and shut it off for 10 min. start unit back up and runs good for a few min, than back to shit, with not check engine light on. now first off I did a valve adjustment, no change, checked for the oil leak at the injectors all look good, test the power to injectors all good, than I checked the exhaust temp at the manifold and this is what I got, #1 183 F, #2 203 F, #3 217 F, #4 230 F, #5 223 F, #6 206 F. now from what I get out of that is I have a problem with the mechanical side of #1 injector, and possible #2 and 6, I assume that the temps should be close to the same. would you say that the #1 injector fail? now I just started out on my own and do not have a diagnostic computer, and hoping I can figure it out with out taking it to dealer to get it checked out. I do know that if I change an injector than I will have to take it to the dealer and have them calibrate the injector. if you have any leads for me that would be much appreciate. keep up with the good vidsthanksnoel
Hi I have a 2006 t800 Kenworth C13 cat. Come off the road in the truck stop . Motor won't come up to speed. Had it towed diagnostics done tech said it was injector 4 and 6 . I replace them my self. Still doing the same thing starts hard idle is fine won't come up to speed. I run the flash test that was in your videos with the check engine light. I have a 6-4 code, 7-2,7-3 and 7-4 code.. oil pressure is 40 lb on Idel and 62 when accelerates.
40-50 psi at 1000 rpm 475 cat c15 6nz. Going to replace fuel filters/flush diesel and add some injector cleaner with new diesel and also replace the Fuel pump check valve, Atmospheric pressure sensor, Boost Pressure Sensor, OEM Caterpillar Oil Pressure Sensor. What else should I do?
My C7 is wasting alot of diesel! 7mpg ... I'm only working for diesel ...Any suggestions on it ?? Thank you
We have Cat 3116 in a gmc 96 C6500 it has two tanks and it has a connecting line from passenger to the driver side tank but it's only drawing from the driver side tank and leaving the other full. I have dropped tanks cleaned them.
Thanks for this video, am having a challenge on a marine CAT C4.4 engine, the fuel rail sensor switch, if it's disconnected the engine starts, but if connected back it won't start-up, a replacement was made and it did start, but later won't restart again, please kindly help, if there is something else am not doing right. Thanks a lot.
Holy cow, this was a year ago, did you get it figured out? I'm having starting issues with a 6.6L CAT engine 3116. It requires air pressure into the return line to help with pressure, once started it runs though. I have been told the problem is a faulty check valve on the return line causing leak down which allows fuel lines to get air in them.
My 3126 lost power and won’t start after u cut it off changed fuel filter won’t start take the fuel filters off it will start
very great video! I have a 3126 in my motorhome. I'm planning on ditching the lp generator and adding a Cummings quiet diesel generator which I just purchased. I need to tap into the fuel system for my supply and return on the generator but do not want to mess with the pressure of the motor. By watching this I should be ok tapping into the supply before the primary filter of the 3126 and the return after the pressure regulator. Do you see any issues with that idea? Thank you
+john67elco You should be okay as the generator shouldn't pull that much volume of fuel, but the issue you may have is the inlet line will be under vacuum with the engine pulling the fuel to the main engine.
+Adept Ape oh yes good call I didn't think about the vacuum I'll look into a fuel check valve so the generator supply doesn't get the prime taken away from the main engine running
+john67elco would you know if the fittings off the cat 3126 filter are an-6 fittings? Trying to figure connection points to figure the Y fitting for the supply to generator thank you
I recently bought a 2001 GMC Topkick C6500 with a Cat 3126 engine. The original vehicle order form, listing all equipment options states "Fuel Water Separator Raycor". I can not find the separator and / or it's drain valve. Anyone?