Volvo Penta 5.0 GLBY engine dies out

[cargarci]

Volvo Penta 5.0 GLBY engine with SX-M Sterndrive.

Engine starts every time with no problem after a while in neutral stalls. I have taking it in the water and could run fine at different speeds with no problem but then suddenly it stalls and dies. It starts right up and runs for another while and does the same.

How can I troubleshoot myself PLEASE!!!, I have spent over $6k now everytime the dealer works on it the problem dissapears for a while and then comes back.
here are the things they have worked on so far;

1. Changed distributor cap, rotor and cables.
2. Did a compression test (tested out ok).
3. They checked the fuel tank. (good and clean).
4. They did a Fuel system test (no restriction, good fuel flow).
5. Shift cable was corroded, (replaced).
6. Several cables studs or terminals corroded (replaced).
7. Replaced carburator kit.
8. Volvo Penta 5.0 GLBY engine with SX-M Sterndrive. Engine was stalling and backfiring. I took the boat to the authorized dealer and they did several things;

Should I start from scratch myself. What should I do?

Any help greatly appreciated as always.

Thanks.


Carlos

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

When it dies, is it like it runs out of gas and sputter a bit, or just shut off like you turned the key off?

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

its like running out of gas, sometimes I can keep it from dying by moving the accelerator up and down while dying.

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

Has anyone done a fuel pressure test? There is a test fitting to hook into the fuel line going to the carb so you don't have to cut the line.
There has also been a few here that found the screen in the inlet of the fuel pump partially plugged. There was paint on the filter housing that is coming off due to the ethanol fuel and plugging the screen.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Yes. They have done a pressure test in the past. But, at this point I am willing to try anything. Is the fuel pressure test something I can do (what do I need, a gage?), how do I make the test fitting?

I am not scared of trying anything but need guidance, please!

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

You just have to remove the metal line between the carb and fuel pump. Adapt a hose to the fuel pump and the carb. Put a Tee fitting in the hose at a convenient location and hook a fuel pressure gauge to the tee in the fuel line.

Then run the engine under load (out on the water) and see what it says for fuel pressure when the engine stops running. Should show between 4 and 7 psi.
If it drops way off and the engine dies, you know you have a fuel problem.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Thanks, Can I buy these parts at Autozone?

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

Have no clue, never been to an Autozone.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

hehe, ok thanks. I am getting all the parts to perform the test. Will post afterwards.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Ok I put the fuel pressure gauge and the engine started ok with 5 psi. after a while it started flickering between 4 and 5 (all the time in neutral idling). After 5 minutes it dropped to 0 and the engine ran for about maybe 30 to 45 seconds and died. (I thought the gauge was bad reading 0 since the engine kept running).

What now?

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

Pull the fuel pump and look at the screen in the inlet of the pump.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Thanks. I will take a look tomorrow morning but I dont recall seeing a screen in this fuel pump when I replaced about 6 months ago.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

I went this morning and pulled out the fuel pump, 3/8 hose, fuel filter and everything in between to inspect. The fuel pump had no dirt or debrie on either screen. I blew air thru the 3/8 hose and no obstruction there.

Could it be the anti=syphon valve?

Also I noticed this morning that the engine starts right up with no fuel pressure (I guess with what is left on the line) and then dies after 60 seconds. Then after I start the engine and bring the rpms to about 1200 the pressure builds up again to about 5 1/2 psi.

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

Could it be the anti=syphon valve?

Sure it could be, but in your original post you posted this,

3. They checked the fuel tank. (good and clean).
4. They did a Fuel system test (no restriction, good fuel flow).

I sort of assumed it was looked at too.
Try this.

Hook up a remote fuel tank (outboard tank) directly to the inlet fitting on the fuel filter. Then see what happens. That elimates the complet tank in your boat.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Ok, went and put an external tank and took it out for a ride (very scary, waves at 8ft today here in Puerto Rico) and the engine died once at 2k rpm and consequently at lower speeds. At all times the fuel pressure was at 5 1/2. after engine was off for 15 seconds then the pressure will drop to 3 and 2 psi.

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

I think I would be inclined to recheck the float level in the carb.

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Thanks DonS, I really appreciate your time helping me out. I think checking the float level is for a mechanic now. I will post the results after I get someone to check it,

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Ok, got the carburator out, bought a carburator rebuild kit anf brought it to a carb shop. The guy said it was very dirty and that the need;es were clogged.
I put it in a few hours ago. The engine runs better but now it misses and backfires. It shutdown twice on me. Also, it backfire more often at full throtle,

 

[cargarci]

Re: Volvo Penta 5.0 GLBY engine dies out

Hi Don, anymore ideas?

Thanks in advance!

 

[Don S]

Re: Volvo Penta 5.0 GLBY engine dies out

You probably need a new carb. Many, many times marine carbs are not rebuildable due to corrosion.