How To Change a HEUI Pump. Cat C7, 3126, and C9 

yeah great videos..their isnt much diesel stuff like this on youtube im glad i found your channel

Ape I love your videos, starting a Diesel Fitting apprenticeship soon and all these videos are an unexplainable amount of knowledge! Thank you :)

Great videos! I'd love to see a C7S Acert walk around and regen system diag and explanation, the common rail C7S.

Did my first c7 HEUI pump the other day, same symptoms as this one. Great video, thanks for the tips!

Saved my day, Thank you!🫡

Great video man!, love all these videos on CAT engines gives me a better clear knowledge.

Loved seeing the 3208 in the Suburban!

Great video definitely explain every step

N thanks for all that you do on youtube to help us out... awesome

Great great great videos! Thank you for what you do

thanks for responding, I can't wait to see that video

Always great info totally appreciate your knowledge man!

that funny I used old mirror bracket just cut it where the bolt went work just fine great videos.

You do not need to remove the air compressor to replace the line. All you need to do is unbolt the power steering pump from the back of the air compressor (leave the p/s lines on) then all you do is remove the back side it's held by 4 nuts (13mm wrench) then you have access to the 2 Allen head bolts that bolt the line to the block. Then you replace the O-ring on the block and reinstall

You the Man!!! Thank you for the video!!

*Great video man! I watch a lot of them because I run two trucks with these engines. Just had a pump go out. Thanks a lot* #WorldsOkayestFarmer

makes sense to remove/replace the compressor and oil line when doing the pump anyway.

thank you for this video

Nice information

thanks for the info I'm been learning a lot i appreciate

Very good

word of advice make sure to remove add thread locker and re-torque the drive gear nut. have found them lose or to become lose after a few hours of running. also had some come in with a lose nut on ones just replaced by freightliner.

Thank you sir

such a pro!!!

The oil accumulator on the HEUI pump hold approximately 3000-3500psi of oil pressure to fire the diesel injector during cracking of the engine at startup. Hard start will occur if the accumulator can not maintain 3000-3500psi.

Oh very good video tankyou

make sure and have new lines when doing this procedure. and this is easy. try doing on a c9 marine engine

I'm changing the pump on a 3126B. Different style than what's on the video. The oil line that comes up from behind the compressor is solid steel and makes it real tough to get the pump out.

I have changed several of these on C7s

I'm about to purchase a 2005 Freightliner sportchassis with a C7 cat motor. Under 100k and lots of good maintenance and service records. My question is I read so many issues with the heui pump dumping metal into the fuel system and causing injector damage and replacement. Why hasn't anyone added a high pressure inline fuel filter from the heui to the fuel rail ? Is that even possible ? Very new to Cats, all my toys have DD 6-71TI's. Great video and thank you.

Replacing the injectors is only necessary if that solenoid itself fails and leaves metal shavings around the solenoid? Can contamination be seen through some of oil lines going into the cylinder head? Thank you for the informative video...

thnaks man really thanks

Thanks for this video! A big help. Especially the part about telling us that this unit is not timed. A nice little fun treat there at the end too! I am going to look at some of your other videos now. I'm hoping to possibly learn more about the engine/fuel injection difference between say a 190 HP 3126E, and a 330 HP engine. I have one Truck with a bad 210 HP 3126B (70 pin), and I'm hoping I can more or less easily swap in a two year newer (70 pin) 3126E, of 300 or (EMS) 330 HP. I'd sure love to learn more about how Cat gets 800 ft/lb, and 860 ft/lb rating out of the same engine. It seems they are selling a high, and low torque models?

Josh, at 1:11 mark is that the upgraded high pressure oil supply line(solid steel vs. steel braided hose) you talked about upgrading in the get to know your 3126 video. Thanks. Trying to tell if our 3126e hose has been changed.

Thankkkkkk you, you saved my ass.

I enjoyed the video and learned a lot, thank you. Could you tell me the part number for the sealing O ring on the pump. I ordered a pump but it did not come with the O ring

How about a video of the 3126 with the bolts on the back of the heui pump

hi sir hope you well thanks for making very good videos its a really big help . i like to know if you have made the video to replace the common rail fuel pump on C7S . please send me the link or just one qustion about the common rail fuel pump have timming or not ? thanks

Good morning sir

really appreciate videos,, I have a c7 cat , and have No Fuel pressure , can you help

Your videos are very good thanks you. I would like to know what I need to troubleshoot my engine? I have a 3126 installed in my boat and it is loosing power. Thanks Darrell

Josh, the head on that new Heui pump looked cracked on the front (above the separation of the head and case), where your left hand is holding it. ??

Can you replace a square head heui pump with the round head heui pump. I believe in a different video you said the round pump had less problems and you could replace the driver separately from the rest of the pump for a lot less money. I have a rv with a 330hp 3126e. Thanks

This is great! Man, your videos are great. The HPOP on my 3126 diesel has a corroded case...I'll be into that job sooner or later. "Adept", my question is this: Is it possible to find JUST the metal DOME for my 1996 3126 HPOP? I knocked off the rust and wire brushed it, and hit it with some Rusteoleum Rust Restore paint, but I'm thinking sooner or later that's gotta be replaced.....I can't see to find just that part.... the "DOME" for the 96 3126 HPOP.

Hey Ape!! Good tips you give here on your videos!! But i still have an issue i got this RV with a Cat 3126 and it wont start just cranks the tach does move and the oil press does move too. A previous tech says the fuel injector pressure is 200. What can you suggest it is?

Do you have a video about replacing the flexible oil line going to the HUEI pump? The replacement line is a rigid steel tube assembly.

Hey brother! Love you videos I’ve being watching all of them, now I have a question about the heui pump I remove the lift pump of the heui and I didn’t use the so call special bolt and all my springs and stuff I. The other side came out, I get to put it together but I heard that once all the springs and parts come out the pump would not run the same and I have to get a new heui pump?

I own a motorhome with a C7. I read in an RV forum that it is a good idea to clean oil sludge from the HEUI pressure regulator valve on an annual basis. Your thoughts on this? If it is a good idea, would you be willing to post a video showing us how to do it? Thanks! Love your videos!

Can you use the other style huei pump that's available. Does it matter?

I just replaced it but now I’m loosing oil through the blow by could it be related to the heui pump or any other suggestions highly appreciate it

Does the high pressure supply line to the head have any O rings or just the ones that sit on the connectors? If you could help please I’m in desperate mode I have had issues with this for about a year

Hey great videos can't thank you enough! I have a c7 in a f750 truck runs great until the temp gets close to 180 then the truck struggles to build/jumps the rpms only when driving and idles a little shaky could this be a cause of the heui pump?

Hi, Can i ask about C9 engine, If we change new injector, It need also re-incoding the injector? Thnks for d answer plz,,,

thx for the lecture sir, i also have a problem with one of our wheelerloader 996h, showing three erro ,engine oil pressure,coolant temp,air flow, and engine has no power, pliz advice thx

My parents have a 2002 frieghtliner motor home with a 330hp cat 3126 every was fine with it until my dad fired it up the other day it ran for a minute and then shut off the fuel filter I drained the cycled the key a few times but it will not fill back up with diesel but fired up with a tiny bit of starting fluid any recommendations

Could you tell me where the fuel pressure regulator is on this engine?

Good evening, I have a cat 140K year 2010, he is blowing white smoke through the engine breather, and he reissued valve guides, engine block, compressor, he changed rings, checked the engine liners. Bearings, even changed oil pump and pressure pump, but the problem persists, white smoke is still coming out of the engine oil nozzle. What I can do, changed almost everything, I only need to see the turbo, which advises me or which believes the problem.

I have a 3406b. The huei pump? Is leaking oil. Can I rebuild it myself

Why is my oil not getting oil to the rockers and not starting?

I have a C7 in our RV that is now popping the CEL "94-1 Low Fuel Pressure Warning (63)". Does this sound like my pump is going bad? If so, how would I change it in a pusher Freightliner chassis? I'm pretty mechanically inclined but it sure is tight in there! Help from all is welcome please!

What's the trouble shoot for this ? Why this pump had to be replaced what's the simthoms???

Im about to change diesel filter can you tell me how to prime it or es electronic primed the engine is a cat 7.2 C7 hope you can help me!

So I have a code 63 once in awhile what's ur opinion on changing the transfer pump on the back of huie pump?

Can we open IAP control valve. For replacement???

Hi. I have a 05 C7 not getting fuel. Ran great before it got 20 below a few weeks ago. Changed filters. Did not help. Ordered new fuel regulator. They sent the wrong one. Just took out the old one and tried to start. No fuel is coming out of the hole. Fuel gauge is showing 0 psi. Time for a huie pump or is there something else i can try first? Thanks for your help.

thank you for your reply when you open up the lines and flush the system you will be flushing out the oil side will it be metal in the return lines for the fuel tank I'm trying to figure this thing out I am a gas mechanic this is all new to me thanks

I put a 3208 cat in a 68 international scout 800

Is that fitting an stc?

I'm trying to purchase a 2005 motorhome with a 350hp C7. This whole HEUI pump has got me scared. Is this a great concern?

Hello AA, It's Mike from the Jpaydirt channel. We are considering switching out the old fuel injection system on our current build called old kenny with a 1693 in it. We would like to switch it to a high pressure common rail system and wanted your opinion. Thank You, Mike

great videos, keep up the good work. I have a c15acert bxs, does the overhead videos apply to that engine and the injector replacement the same? thanks

If you do this repair, is it necessary to change the injectors too?

I replaced the transfer pump back of heui pump due to an oil leak on cat c7. Now I have an oil leak on the front part of the heui pump. Was wondering if the gasket is able to be replaced or need a new heui pump. Thanks

I need help installed new injectors, fuel rail filters lines etc and still wont start

Is that solenoid inside the pump like an IPR valve? Seems like it has the same function.

Hi adept , I have c7 -190hp-freightliner straight 5ton truck . Problem - diesel in oil and low oil pressure Cat guys changed o rigs of injectors and now they are changing transfer pump . I am not getting any code. Cat dealer guys also confused about this dilution. Plz advise Thanks

Hi Adept, can you explain the difference between C7 and C9 injectors? and can the c9 injector be used in a c7 engine?

great videos,have you ever seen a cat 3126 in a 1999 chevy c6500 tach won't work,cat et shows engine rpm but the tach in the dash doesn't,no faults in ecm.I also have a 2003 ford f650 witha 3126 that cat et will not communicate with the ecm,engine will run but et will not communicate through the 9 pin in the cab,i don't have a diagram for the 9 pin in the cab to the cat ecm.

Okay I have a question I would appreciate your help I have a c7 in a 07 c7500 it is leaking oil from between the fuel transfer pump and the huei pump what is the process to stop it is there an o ring that seals it and do I need the fuel transfer pump removal tool from cat thank you for any help you can provide me

Long shot but I have a c7 that looses fuel prime if it sits more than a day. What could this be??????

These videos are great going to leave a donation for you my question got a 98 Peterbilt 330 dump truck with a 3126cat 210hp s/n#1wm13822 230k it will miss under load over 1500rpm only at cruising or pulling a hill while pulling trailer or hauling dirt empty it will miss very little you don't notice it very much taking off from a light is fine till about 35mph then it starts the tach needle jumps around when it's missing any help is very appreciated

Hi What's the voltage I should read going to the fuel pump? I'm only getting 10 volts crank but won't start

Hi Adept Ape, I have just found your channel. At the moment I have a problem with a Cat 3126 engine mounted in a Claas combine. The oil line to the top of the motor was pulled out of the housing of the pump. The motor stopped immediately and some oil got out. We are still waiting for a new pump, because I am from Germany and nobody here has a new one. We had to order it from the US and are still waiting since one week... Just some questions: Do you think, the engine can have some damage? The engine has 2000 working hours. Do you have some experience whether it is normal with this age? Many thanks for any reply.

I have a 2000 F750 with 3126, truck recently started to lose power after 30 minutes of use and reduce to 10mph with CEL. Changed high pressure oil sensor, still no luck, mechanic says high pressure oil pump should be changed, seem like a logical next step? I should mention shutting truck off and restarting clears CEL and problem goes away for 5-15 minutes until it loses power again, seems to happen at lower speeds not highway cruising. Thanks

3116 fuel pump does it have to be timing

Hi Adept Ape, I have a 3126B 8YL49553 330hp in a motorhome we had a lighting strike close to our house and ever since I can't get the rv started. The coach was plugged into the house for power like it always is. A cat tech guy came out and hooked directly into the ecm and said it was dead would not communicate with his computer. I ordered a rebuilt one from a company in Texas with life time warranty hooked it up and nothing same as old one. Have a pressure gauge hooked up to the high pressure rail and all I get is 200 psi, I know I need at least 850 psi to get it to fire. checked the fuse and ground and cleaned both, question is did i fry the new ecm is there some way to check wiring to find a short or what do i do. On a side note the lighting strike also took out the circuit board on the water heater. Help thanks Ralph

El vídeo se ve bueno.... Pero para las personas que no sabemos inglés sería bueno que viniera subtitulado

I have a question. I have a 3126 in my bus that has this same Heui pump. The rubber feed line is leaking a little (seeping). Is this something I need to address immediately, or is it ok to run it for bit while I gather parts?

I have this code actuation pressure output fault ?????

Why would be the reason for changing the HEUI PUMP

I have 3126 just changed Heui pump truck will start now but it will cut off in 2/3 min Need help please

I have a 2003 fl 60 with a 3126 E motor with a C 7 pump not a round top is this a better pump And can you add a jake brake to this motor

I have a 3126E in a 2004 motorhome. The HEUI pump looks exactly like the one you refer to as on a C7 engine. Is the 3126E similar to the C7 injection system? I know it's the last motor design before they went to the C7.

Hey man got a quick question I got a c7 not firing all injector seals are leaking on the the top .. replaced all orings on all injectors tourque to spec and still leaking .not allowing oil pressure to build up and fire ..could I have a bad head ? Or maybe the bolts are too stretch 🤔,and not getting the right torque ?

My Sencer on top of heui pump is lose and has a slow oil leaking around it is that a problem ?

Is the valve on top replacable . do they go bad?

Can someone tell me the size of the opening on that tool? Trying to locate one for an FMTV in Germany, it's an impossible task. Need to fabricate.

Where can we purchase c9 engine heui pumps

is the air compressor timed on a c7?

Have you ever seen where after changing the heui pump you suddenly have high crankcase pressure causing oil out the vent tube?