Required Manual Priming to start 2500HD

Talbert · December 19, 2005

Brother-in-law was nice enough to top off my 2002 2500HD 37K mile Duramax with unleaded. Had truck towed in and they dropped the tank, drained fuel and replaced fuel filter. Picked up truck and it worked that evening. Went to start following day and it started and died 3 seconds later. Primed system at fuel filter and truck started. This was required every time the truck sat for more than 4 hrs. After a week of priming to start I killed the batteries trying to start on cold morning. Truck was towed in and techs reprimed system and claimed that there was no other problems, no repriming required and no DTC's found. They state that they periodically started the truck without issue for two days. I picked up my truck and the following morning it died breifly after starting. Got out reprimed and it started. Any ideas? Dealership claims that the next move would be to replace the fuel pump which I have been told is pricey and would not be considered under warranty due to the unleaded incident, and that they are not 100% sure that it would fix the problem.

Talbert

GM-Tech · December 19, 2005

When you use the hand pump on top of the filter, do you loosen the little black plastic screw and if so, do you get a lot of air out of it?

We've had several diesels in that had been filled with gasoline and never had to replace a pump, but that's not to say it can't happen. There's plenty of diagnosics that can be done before replacing the mega dollar pump.

Talbert · December 19, 2005

noone had mentioned loosening a black plastic screw. How loose does it need to be to allow for fuel or air to escape?

GM-Tech · December 19, 2005

Several turns. I usually take it completely out, but that's not really necessary. It has a bleed hole in it.

Just the fact that you didn't remove the screw before pumping doesn't mean that loosening the screw will solve your problem. It'll just let you see if there's actually air in there.

Talbert · December 21, 2005

Thanks for the help. Following morning I went out loosened screw, primed till fuel came out, and it has worked since. I wish the dealership would have told me the same the first time it occured, or at least when I took it in the second time.

GM-Tech · December 21, 2005

I'm not sure how that would fix it. Even if you pumped it without taking the screw out, once the engine is running, and assuming it keeps running, what little bit of air there was left will purge on its own.

But hey, as long as it works.