[kvanausdal]

Four times now in the high summer temperatures (110+) of Phoenix and Yuma, my LLY (60K miles, no performance add on's) has failed to start after stopping for a short period of time. Engine and transmission temps were normal. I bled and primed the fuel filter and that fixed it on failures 1, 2 and 4. It didn't work on occurrence #3, so I got towed to Chevy dealer; first thing the tech did was bleed the fuel filter and it starts (grrrrr!). He put it on the computer, no codes, no advice on the problem. I changed the fuel filter between #2 and #3, and I just changed it again last week.

So, any ideas on my problem.
TIA, Keith

 

[Diesel Wanna Be]

Don't think a diesel can vapor lock, especially stock.

There's several components that can cause loss of fuel prime.

1. Shrader valve by alternator.
2. Fuel filter or filter head.
3. Cracked fuel pump pickup.

Those would be the things I'd check first, in order of expense and ease of fixing.

 

[Ron Nielson]

One more thing to add to list: Cracked (or improperly installed) WIF sensor.

 

[JC1843]

The most common problem is the seals in the fuel filter head-- the high heat in that area of the engine, cooks the seals and allows air into the fuel system.

Several supporting vendors have a seal kit to re-seal the filter head. Check the vendor list. GM does NOT service the seal parts-- only a complete filter head--$$$.

 

[kvanausdal]

Thanks, Gents! I know it's not really vapor lock, but same symptoms. Won't put clothes pins on the fuel line! (Old guys can relate). I'll work through the lists, when it cools off to the 90's here in Phx.

 

[Ron Nielson]

When was the last time you cleaned your fuel cooler, under the truck near your fuel tank? Hot fuel causes many otherwise unexplained problems and cleaning your fuel cooler at the self service car wash is a very easy thing to do. Cost? Maybe $1.25 or so. If it works, great. If not, you aren't out much.

 

[maxboost]

could also be the FPRV needs shimmed

 

[kvanausdal]

Fuel cooler

When was the last time you cleaned your fuel cooler, under the truck near your fuel tank? Hot fuel causes many otherwise unexplained problems and cleaning your fuel cooler at the self service car wash is a very easy thing to do. Cost? Maybe $1.25 or so. If it works, great. If not, you aren't out much.

Doh!! I didn't know that I have a fuel cooler. When the concrete cools to something below 100 this evening, I'll get out the pressure washer. Years ago, I printed "the real" maintenance schedule for my LLY from this site, I sure don't recall reading about this maintenance tip.

Was just on Merchant's site to order the fuel filter head rebuild kit. Any challenges to installing the seals? MA doesn't say whether instructions are included.

 

[Ron Nielson]

I didn't check the Merchant site, but here is the YouTube link for the filter head rebuild:

http://youtu.be/9boIwwN-AHA

 

[Diesel Wanna Be]

All issues with fuel starvation can be solved for a little bit of time and less than $150.00 with an economical lift pump setup: http://www.dieselplace.com/forum/showthread.php?t=424968

I used the Carter hi-pressure pump which requires a regulator. You could just as easily use the 8PSI fixed version pump without a regulator. Any vacuum leaks would quickly become fluid leaks, and you would make sure your CP3 pump never starts dry.