95' omc/volvo 5.0L

[scotte]

I have a 95 omc cobra, volvo, 5.0L HO with multi port fuel injection, I just replaced the high pressure fuel pump and I'm only reading 20psi on the fuel rail by the front injectors, does anyone have some idea of the pressure should be. Thank you for your time and info.

 

[a.d.mobile]

Re: 95' omc/volvo 5.0L

39 +or- 3psi key on engine off. 31 + or - 3 psi idling,will motor start? if so pull vaccum line of fuel pressure regulator and see if pressure goes up. did you check for fuel restrictions? you must check pick up and antisyphon valve in the tank this is uaualy the problem. look at the ball in antisyphon real good it does not take much. do you have a remote tank? hook that up and see what happens. outboard tank works great dont wory about mixed gas no biggie.

 

[scotte]

Re: 95' omc/volvo 5.0L

Thanks for the info. I pulled the anti siphon valve apart, so it is not anything to consider anymore. I didn't pull the vacuum line but I will try that. If the pressure dosen't raise is that the tell tale that the regulator is bad?

 

[a.d.mobile]

Re: 95' omc/volvo 5.0L

it wont raise unless engine is running will it run?

 

[scotte]

Re: 95' omc/volvo 5.0L

Yes, it runs fine at idle and low rpm, but if you jump on the throttle it coughs, ckokes and spits, and the fuel pressure just sits at 20psi. If you ease the throttle it will rev up slowly.

 

[a.d.mobile]

Re: 95' omc/volvo 5.0L

check the oil is there gas in it?

 

[scotte]

Re: 95' omc/volvo 5.0L

I took your advice and double checked the supply line, and ran it off of an external tank with a primer bulb. With the engine running the pressure would sit at about 18 psi, but i could force it to about 33 psi if I would keep pupming the priming bulb, but the pressure would bleed down and return to the 18 psi. I also pulled the vacuum line off and there was absolutley no change in any way. Do you think that the regulator is justplain stuck, or shot? I did't notice anythig wrong with the oil, it looks really good and golden color, and dosen't smell.

 

[a.d.mobile]

Re: 95' omc/volvo 5.0L

was there vaccum on the line when you removed it? engine running.

 

[scotte]

Re: 95' omc/volvo 5.0L

Yes, it was running, and had a pretty strong vacuum by feel, I didn't have a gauge.

 

[scotte]

Re: 95' omc/volvo 5.0L

Just for info, the problem should have been resolved the first try, I was given the wrong high pressure fuel, it was a lift pump for omc, johnson/evinrude, not a high pressure fuel pump. The difference being supply pres. lift pump is 18#, vice the high pres. being up to 40# supply. Thanks for you trouble shooting assistance.

 

[a.d.mobile]

Re: 95' omc/volvo 5.0L

no problem, i was going in the gauge reading wrong on the wrong pump purchased glad to hear you are on the fun side of boating again!