7.4 GI PWTR EFI bleed help

[TJ 755]

I just re-powered my 1990 maristar 240 SC with the referenced engine i picked up as a low hour take-out. The job was a piece of cake, same block as before so everything bolted right up, picked up a instrument/ ignition harness and boom fired first crank.
Let her idle for a sec, double check fluids and temp. Fire back up, purrs like a kitten and then slowly starves and dies. No big right? probably air in the EFI system, talked to a guy at Redmond Sea-ray and he said yeah that's common just keep firing it up until all the air is out and the system is fully primed.
Now I cant even get her to pop, good fuel at the LP and HP pumps. There is an odor of old gas when i pulled one of the spark plugs. Not sure what the next step is now. I don't have the engine s/n handy but a believe it is 1999ish model. I downloaded the EFI diagnostic manual from one of Don's links today at work but not sure if it is the correct one. The book shows both pumps mounted fwd and my HP is aft.

 

[Don S]

Re: 7.4 GI PWTR EFI bleed help

Which manual did you download? It came from the WT section, right?

 

[TJ 755]

Re: 7.4 GI PWTR EFI bleed help

Yes it says 1999 "WT" models. 402 pages so I did not print it out. Maybe I will try and move it to a lap top I can bring into the shop. Trying to get a fuel pressure gauge and start there. I just checked for presence. Really don't want to pull the tunnel and mess with the rail and injectors.

 

[Don S]

Re: 7.4 GI PWTR EFI bleed help

Just print the pages you need, not the whole manual. The manual is also in sections. be sure you are in the right section for your engine.

 

[TJ 755]

Re: 7.4 GI PWTR EFI bleed help

Looks like it was the high pressure pump. It was getting 12V but not pumping. Pulled it off and bench tested with 12V and its locked up. Blasted in the intake side with compressed air, there was alot of resistance and then it blew a wad of gas and crap. Put 12V on it again and no hum or spin. Strange that it ran for a while.
Chasing down a new 3857650. Most places are $150 -$180.
Also there was some debris down in the vapor separator thingy. Would have needed to really been shaken up to reach the pick up tube though.

 

[Don S]

Re: 7.4 GI PWTR EFI bleed help

You need to clean out the VST and use new gaskets and orings on the fittings. I would suggest you pull the low pressure pump and check that screen also. Seems there was some paint on the filter housings isn't holding up against the ethanol fuel we now have. Replace the fuel filter also.

 

[TJ 755]

Re: 7.4 GI PWTR EFI bleed help

Yeah I am cleaning out that vapor float bowl and definitely replacing the filter and the o-rings were badly deteriorated. Do I need the red O-rings? is that a CG fuel/ fire thing? I have a universal kit of black ones.

 

[Don S]

Re: 7.4 GI PWTR EFI bleed help

Get the proper orings, if not the correct material, they will swell up and crumble.