M1085a1 Wrong Fuel, Now Won’t Start

[TurboTerry]

Scratch that, not the fuel shut off, the IPR.

 

[scottmandu]

Send it to auction!

 

[73m819]

Ok, it NOW starts on either, that changes things, look at the pick up pump, make sure no scoring/burnt/bad O-rings/seals, REPLACE the O-rings in the primer, worse comes to worse REPLACE the WHOLE primer unit, next then pull the ip you have nothing to loose at this point, again look for burnt/scored/ect. It is not the injectors per say, they WILL work somewhat even burnt, same with the valves. SO back to the ip which is LUBED by engine oil NOT gas, very few IPs can handle gas as a lube because it is so dry/thin which = scoring/ect., also the same thing happens with rings, valves. injectors.

It may be cheaper in the long run to REPLACE the engine or get rid of truck because after it starts AND runs, there WILL more then likely be a bunch of secondary issues to deal with like rings, scored liners/walls, ect..

Good Luck

PS, I would REPLACE EVERY O-ring that you come across.

 

[TurboTerry]

I've done all of that in the last two days. Even replaced the IPR with a known working one even though I saw zero issues with it. Primer has been replaced because the old one blew out the check valve into the filter. Every o ring I've come across I have replaced, just for sanity's sake. The only thing left is the HEUI pump. Idk what else it could be. I have no fuel leaks. Engine has great compression. IPR, fuel Primer, fuel pressure regulator have all been replaced. Injectors aren't leaking and it's not sucking air yet it won't stay primed no matter what I do.

 

[73m819]

All right lets try this,

1--Install a schourder valve (tire inflection valve) in fuel cap to pressurize the tank.
2--Make up a pressure regulator with pressure gauge to fit between the air supply and the tank cap.
3--Crack the fuel line to the ip.
4--Pressurize the fuel tank to about 1 lb. or so.
5--When fuel leaks out of the loose fuel line, tighten it
6--Crack the injector lines.
7--When fuel shows, retighten them.
8--Leave the air supply ON to keep the fuel system pressured.
9--LOOK for leaks, if some found, fix.
--A-Clean ALL connections in the fuel system with brake clean or something like it, then let dry.
--B-Make sure ALL connections are DRY, then put baby powder or flower, ect, (any fine powder will work) on ALL the connections.
----1-The powder WILL suck up even the smallest seep which WILL be easy to see, remember even the smallest seep could be why you loose the prime.
10-Try starting the truck ( on either if needed).
11-IF the truck starts, stays running, look at the lift pump, by pressuring the tank the lift pump is bypassed, It does not take much to burn up a gear pump so the pump spins but not pump. Gas instead of fuel WILL do it in a heart beat.

Try this if things still do not work, we will come up with more ideas.

GOOD LUCK