volvo 7.4 gi been sitting for some time...

[WSUDERMAN]

I picked up a 1999 240 fourwinns horizon that has been sitting for some time and had bad fuel in it. I got it running but it has a rough idle, stumble off idle and stalls. This is all on the muffs (still working on getting the hull ready for a lake test.)

What I have done;
Drained the fuel tank.
cleaned pickup tube and screen.
cleaned the check valve.
replaced fuel/water filter
oil & filter change

Test results -
Low pressure test = 3-4 lbs
high pressure test = 30-35

I think the low pressure pump is bad? Also, what else should be cleaned or replaced?
Fuel injectors?
Regulator?
Distributor?
Plugs?
Plug wires?

This is my first "revival" so any help is welcome.

Wes

 

[GLENN M]

Re: volvo 7.4 gi been sitting for some time...

if your gonna work on it you need manuel,cant assume pump bad check test results with specs,then tune up,if still missing check compression.determine problem then buy parts,but tune up is regular maintenance

 

[Don S]

Re: volvo 7.4 gi been sitting for some time...

You can not go by boat year as the year of your engine and drive package. Unlike automotive where the manufacturer makes both, in marine the boat manufacturer orders engines from an engine marinizer (Volvo, Mercruiser, etc.) So you may have an engine that is older, or even newer than the boat.
What is the engines FULL model number (All the letters) or serial number?

How long is "Some Time"? was the fuel varnished, or full of water or ??????
Have you run any fuel system cleaners through the engine?

 

[WSUDERMAN]

Re: volvo 7.4 gi been sitting for some time...

7.4 GI PWTR OR RWTR (hard to tell)
4110183232
3868949

Also, the fuel was varnished. No water to speak of.

Thanks
Wes

 

[Don S]

Re: volvo 7.4 gi been sitting for some time...

7.4 GI PWTR OR RWTR (hard to tell)

It's PWTR, The P indicates it has power steering.

Here are the manuals for the WT model, (It is a 99). http://www.4shared.com/dir/14518373/c484ddd4/WTsharing.html

If the fuel was varnished, I would imagine that varnish is in everything that had fuel in it. The lines, filter, strainers, injectors, pump, you name it.

 

[WSUDERMAN]

Re: volvo 7.4 gi been sitting for some time...

As always, Thanks Don!

I noticed your join date was 2004 but i would swear you helped me with an OMC 800 I had back in 2001-2002?

 

[Don S]

Re: volvo 7.4 gi been sitting for some time...

Probably someone else, I know very little about the stringer drives, and hope to keep it that way

 

[WSUDERMAN]

Re: volvo 7.4 gi been sitting for some time...

Just wanted to update on the fuel/running issue-
1. Pulled the fuel system, tank to injectors and cleaned everything.
2. Replaced both the fuel pumps.
3. Replaced plugs
This has it running pretty well. Much better than before. I still have a bit of a rough idle and a stumble on accel. The power is good once it's off idle and will run to redline no prob. If it was a carb I would be looking at the accelerator pump, but its not so here I am, any ideas?