Reply
Highlighted
Super Contributor

Re: C-7 Injector "Failure"

The HEUI pump originally had only one bearing in the drive end, which caused some problems due to the high loads the bearing experiences. The pump was redesigned with a double-cone bearing which, solved the problem. Caterpillar recommendation was 10W30 Cat oil or 0W40 Cat synthetic oil to prevent future failures.
New member

Re: C-7 Injector "Failure"

I own an '05 Newmar, it sits on a Freightliner chassis powered by a 350hp C7.

 

I have meticulously maintained all service intervals well within the limits, only problems I've has was the engine has overheated twice in it's 70k miles climbing hills, warning lights came on and I immediately cooled it down.

 

Last month, at 70,000 miles the HEUI pump failed and sent metal through the injectors dropping cyliners #5 & 6. For $6K, the Freightliner shop in Tuscon quickly and professionally installed new injectors and installed a rebuilt pump from CAT.

 

 

All's well now, EXCEPT I have no explanation why this happened and no confidence that it won't happen again. Everything I've found online says it's a well known problem, but no suggestions on how to keep it from happening again.

 

Can you give me advice on what if anything I need to do to keep this failure from happening again? 

New member

Re: C-7 Injector "Failure"

 I'm going through the same thing right now. My mechanic brought over the computer scanned my engine the only thing that came up were two codes saying that there were two faulty injectors. So now I'm waiting for the injectors to come in because he told me That they are special order. What does something like this typically cost?

Contributor

Re: C-7 Injector "Failure"

Thanks  Cat_tech.  That is pretty much what I summized.  I am hoping it was mechanical on the poppet valve side and not my HEUI pump starting to go which checked out okay.  Gave me a good opportunity to have top end work done.  I think I was told only one or two valves were "slightly" out of adjustment.  FYI.  Even with this I am still a tried and true believer in the CAT engine so that should be testimonial to how satisfied I am with the product. 

Trusted Contributor

Re: C-7 Injector "Failure"

If the failure was electrical then it would show up in the computer as a fault code.  It was most likly a mechanical failure.  Either on the oil side of the fuel side.  If it can not produce enough fuel pressure to have the correct valve opening pressure and that will effect spray pattern and timing.  Looking at it you will not see a failure unless it split a tip, then you would definitly know you had a problem if that happened. 

You let up, you lose
Contributor

Re: C-7 Injector "Failure"

Thanks Nick.  I attempted to snag one of the bad injectors to see if I could determine the failure method but was told they were turned in for core.

Trusted Contributor

Re: C-7 Injector "Failure"

Not sure about the failure mode of your certain situation.  Ask the dealer to give you a service report and such.  

 

As for your costs- review your warranty statement if applicable to see what it covers.  Its possible you may have some of your charges recovered.  The dealer should again be able to answer this question as well.

 

Hope that helps.

 

Nick C.

Contributor

C-7 Injector "Failure"

I have a C-7 (KAL55907) Manufactured in Greenville in 08.2004.  On recent trip it suddenly lost power and noticable change in sound (tone & volume).  Limped it to exit.  Had it towed to CAT authorized service center(Valley Freightliner, Pacific, WA).  No computer trouble codes found.  Which goes along with what I saw on instrumentation and gauges when it occurred.  Cylinder cut out revealed #5 & #6 weak.  Pulled rail looking for signs of metal for indications of HEUI pump failure. None found.  Replacing injectors for #5 and #6.  Is this "normal"?  Will CAT reimburse me for expense to replace/repair?  What caused the failure?  I have read that an "experimental" type injector was used during this time frame.  Can anyone verify this?  What type and where did they come from injector would fail after 54k miles?  I am a maintenance fanatic especially when it comes to filters so I am assuming it was either a mechanical or an electronic failure in the injector(s).