Colorado Springs Possible major break down.

[Keith Knight]

Yes staying till Monday to turn in the core $1,050.00
Same what is the fail point and why?

 

[GeneralDisorder]

Yes staying till Monday to turn in the core $1,050.00
Same what is the fail point and why?

It is *almost* academic with no parts availability on the 3126 HEUI pump (C7 pumps you can find tools and rebuild kits from China, etc - not so the 3126) - can't get parts AND cat wants the old pump REAL BAD or you lose your core so taking it apart isn't happening either.

And who is gonna risk a HEUI pump that didn't come from CAT? Probably none of us.

Need to find someone at CAT that has loose lips.

You see why the IFS kit no longer interests me? What's it doing exactly? If the pumps are going to pull this BS then it's pretty useless.

 

[Keith Knight]

IFS is just an expensive guarantee not to effect the injectors.

 

[GeneralDisorder]

IFS is just an expensive guarantee not to effect the injectors.

I tend to trust the engineers that built the thing more than some guy buying filter housings and marking them up because HE thinks it's a good idea. I don't think it's a good idea from a safety standpoint at the very least. The CAT engineers put a filter before the HEUI pump on the C7 and they are certainly capable of designing an injector filter if they thought it would help.

Sounded good on paper. His implementation isn't very elegant but it works. The end results though just aren't impressing me, I haven't met the person that saved $5k on injectors - I've only met dozens of people that are $1k poorer. The odds are in my favor and I doubt I'll regret it. Maybe. I takes my lumps when I gets em!

I have long-term concerns over the hoses - not with the pressure per-se but rather the pulsations. It sure would suck for the pulsations to erode the lining of that hose and it all goes into the injectors anyway. Speculation I know but that's the kind of unforeseen BS I would expect from Murphy.

 

[biscuitwhistler37]

Is anyone starting a thread dedicated to HEUI failures/troubleshooting? I've been researching and found some good information, seems like since this thing is kryptonite for both the 3126 and C7, it may be worth having its own thread. If not I'll post findings here.

Glad to see it's running again.

 

[Keith Knight]

It does need its own thread. Make a good title and I’ll add my experience.

 

[ckouba]

Glad to hear you're working through it Keith.

 

[biscuitwhistler37]

It does need its own thread. Make a good title and I’ll add my experience.

Done, thread is CAT HEUI issues, failures and fixes.

 

[Keith Knight]

Update, test drove it today and she ran perfectly! Maybe even better acceleration or maybe a placebo affect?

 

[GeneralDisorder]

Update, test drove it today and she ran perfectly! Maybe even better acceleration or maybe a placebo affect?

That is what has happened with every one I've encountered. It's immediate and dramatic. Change pump - problem gone. Search me as to why?!?

We need to catch us a CAT engineer and ply him with alcohol and my custom brownies...... he'll talk.

 

[biscuitwhistler37]

Update, test drove it today and she ran perfectly! Maybe even better acceleration or maybe a placebo affect?

Could be, but I would bet the timing is more accurate with a new pump.

Edit: How much of an increase in fuel pressure did you notice on the diagnostics afterwards?

 

[GeneralDisorder]

Could be, but I would bet the timing is more accurate with a new pump.

Edit: How much of an increase in fuel pressure did you notice on the diagnostics afterwards?

Guessing it's due to more accurately regulated pressure as requested by the ECM. Accuracy and response time.

The HEUI pump (very conveniently) has NO timing! You just plop the pump in there and crank her up.

 

[Ronmar]

yep, no timing, the pump simply provides a regulated feed pressure as commanded by the ECU. The ECU controls injection timing same as on any other EFI vehicle, using that HEUI feed pump pressure to actuate the injectors instead of a fixed cam timing on the MUI engines so you get variable timing as well as variable injection pressure… a real wonder of diesel technology…

 

[GeneralDisorder]

yep, no timing, the pump simply provides a regulated feed pressure as commanded by the ECU. The ECU controls injection timing same as on any other EFI vehicle, using that HEUI feed pump pressure to actuate the injectors instead of a fixed cam timing on the MUI engines so you get variable timing as well as variable injection pressure… a real wonder of diesel technology…

REALLY helps the cold start and cold idle

 

[biscuitwhistler37]

Guessing it's due to more accurately regulated pressure as requested by the ECM.

That's what I meant by timing, I should have said injector pulse width.

 

[Keith Knight]

Could be, but I would bet the timing is more accurate with a new pump.

Edit: How much of an increase in fuel pressure did you notice on the diagnostics afterwards?

I didn’t get back into the diagnostics.