HEUI Pump Preventative Maintenance

[Petesflhtk]

There are 1000's of the 3126's on the road.. To say they will ALL fail is not an accurate statement.. Change the oil regularly as well as filters. I only use Cat filters...

[Airstreamer6]

Yeah, if the HEUI system "often" failed every 25,000 miles, Caterpillar would have had to recall them early on as a failed design, which it was not. The same HEUI design was incorporated in the first two Ford Powerstroke engines quite successfully and obviously are still being operated today. As Cat noted, some of them fail, but it's the exception not the rule. It's easy to become paranoid and depressed from information on the Internet.

However, I do agree that the post-HEUI filter system is a great idea.

[rbh44]

Originally Posted by rbh44

First I'd like to thank you for your service to our great country.
Now- we have the exact same MH as you.Always been great but now acting up so we have appt.with CAT Garage tomorrow.Not looking forward at all.!!!

Just a quick uptdate to our MH problem.Definite appointment with Holt CAT Garage in Edenburg,Tx Wednesday.Right now hubby says it's in Limp Node.Hoping for an easy fix,but not holding my breath.I'll surely post frollow up after codes are run .Been a trip from Hell this time.Time will tell as long as check book has enough to cover repairs.
Ron,Aletta & one spoiled Scottish Terrier

[discovery39s]

There are more than thousands, more like 10 times. Don't forget about the off road equipment and marine. You mention 3126. Don't forget about C7's....
I hear many stories about how reliable their HEUI is until it happens. The story changes pretty quickly. YES, oil changes prolong all portions of engine components. YES, the Cat engines are built like a tank and I really like my 3126E. I elect to protect $5,000.00 in injectors and oil rail clean out labor when the $1,500.00 HEUI explodes.

However, IF the HEUI design is so reliable then why are there so many forums and postings regarding the failure rates people experience. Why are there so many websites that offer "rebuilt" HEUI pumps. Reliability usually means silence about a product. Lot's of noise out there.......

Try to convince the average off road bulldozer owner to change his oil proportional to 5,000 miles. He would laugh.

[rbh44]

Originally Posted by rbh44

Just a quick uptdate to our MH problem.Definite appointment with Holt CAT Garage in Edenburg,Tx Wednesday.Right now hubby says it's in Limp Node.Hoping for an easy fix,but not holding my breath.I'll surely post frollow up after codes are run .Been a trip from Hell this time.Time will tell as long as check book has enough to cover repairs.
Ron,Aletta & one spoiled Scottish Terrier

Just a follow up & let all y'all know our problem turned out to be 3 bad Injectors .We had all 6 replaced & so far things are ok.We've only driven 20 miles from Holt CAT to the resort so wish us luck on our upcoming 1,100 mile journey back to Ky.If you're ever in South Tx & have problems with your CAT engine I highly recommend Holt CAT in Edinburg,Tx.I want to thank all of you who've offered your expertise knowledge on my questions.
Wishing all of you a safe journey as we travel this wonderful country.
Ron,Aletta & Teri(spoiled Scottish Terrier C0-Pilot
2004 Newmar KS DP 330 CAT Freightliner Chassis

[discovery39s]

Originally Posted by rbh44

Just a follow up & let all y'all know our problem turned out to be 3 bad Injectors .We had all 6 replaced & so far things are ok.We've only driven 20 miles from Holt CAT to the resort so wish us luck on our upcoming 1,100 mile journey back to Ky.If you're ever in South Tx & have problems with your CAT engine I highly recommend Holt CAT in Edinburg,Tx.I want to thank all of you who've offered your expertise knowledge on my questions.
Wishing all of you a safe journey as we travel this wonderful country.
Ron,Aletta & Teri(spoiled Scottish Terrier C0-Pilot
2004 Newmar KS DP 330 CAT Freightliner Chassis

Glad to hear she is humming again. If you happen to experience future injector failures I would strongly recommend having your HEUI inspected. Cat has a service bulletin on the procedure. Did they happen to do an inspection on your HEUI?

Injectors fail on either the fuel side or oil actuation side in a HEUI system. It's important to understand which side fails.

[hlagooty]

You are all making me very nervous here. I am about ready to buy a 1999 c12 powered marquis with 96k on it. The current owner is not mech inclined but has had it serviced regularly. I also drive a c12 MCI bus with 400k on it and have for 4 years with no issues, and their oil changes are at 12k. I hope this issue is alot rarer than it sounds.

[Airstreamer6]

If you're nervous about the HEUI, why not put a thousand-buck investment in the coach and install the new post-HEUI filtering system which is now available. It probably won't be needed, but it's like an insurance policy that will assure a catastrophic HEUI failure would be relatively cheap and easy to fix because it won't cause collateral downstream damage.

Any coach comes with risks. Even the very newest diesel engine designs with the ultra-high-pressure fuel pumps and injector systems have had catastrophic failures caused by a little water in the fuel! And fixing those problems if they occur come with very high price tags indeed.

[rbh44]

Originally Posted by discovery39s

Glad to hear she is humming again. If you happen to experience future injector failures I would strongly recommend having your HEUI inspected. Cat has a service bulletin on the procedure. Did they happen to do an inspection on your HEUI?

Injectors fail on either the fuel side or oil actuation side in a HEUI system. It's important to understand which side fails.

I believe HEUI ch'd ok.We did get a 4yr warranty on the Injectors so if one fails it's a CAT baby.Wasn't cheap but at least we're on the road again.Now in Bossier City,La & she purred like a Kitten all the way.Thanks again for all of you on these forums.I'm just the wife who tries to get the message out to y'all.He does all the driving.Safe travels to all & Happy Valentines Day

[will stevens]

A C-12 with a HEUI system ?

[discovery39s]

Originally Posted by rbh44

I believe HEUI ch'd ok.We did get a 4yr warranty on the Injectors so if one fails it's a CAT baby.Wasn't cheap but at least we're on the road again.Now in Bossier City,La & she purred like a Kitten all the way.Thanks again for all of you on these forums.I'm just the wife who tries to get the message out to y'all.He does all the driving.Safe travels to all & Happy Valentines Day

I called a local cat dealer and they too stated warranty was 4 years on the injectors. I asked if that was valid if the HEUI were to fail and damage the injectors. Answer: Absolutely not. The warranty is for injector failure by itself, not due to other engine component failures.

[Dajoet]

My CAT Mechanic recommended that a Gulf Coast Bypass Filter would prevent a HEUI problem with my C7, so I had one installed. After a year and approximately 10,000 miles, the oil tested normal, so I changed the By Pass filter elements, full flow filter, and added approximately 3 gal of make up oil. I plan to continue this annually.

[Cat]

Good Luck, hope it works out for you.

[discovery39s]

Originally Posted by Dajoet

My CAT Mechanic recommended that a Gulf Coast Bypass Filter would prevent a HEUI problem with my C7, so I had one installed. After a year and approximately 10,000 miles, the oil tested normal, so I changed the By Pass filter elements, full flow filter, and added approximately 3 gal of make up oil. I plan to continue this annually.

Yes, supplemental filter systems will provide excellent additional filtration. This is most important if the oil cooler is allowing cross contamination as noted in many other threads. These type of systems have their place but the bottom line is they cannot prevent contaminants getting to the injectors, HEUI produced or not. Protecting the injectors can save a lot of time, aggravation and $$$$.

You can have the best filtration system on the planet however, if it isn't designed to directly protect one of the most important tight tolerance components (6 of them) in your engine then I guess that's a personal choice of comfort. Sorta like going into a home improvement store that filters the common air handler system with HEPA filters and not wearing a mask under the pretense believing those filters will clean all the air enough to not make wearing a mask to prevent contamination necessary! N95 for me please! Filtering all the common air is great. Filtering at the immediate source is the best possible scenario.

Stay safe!