5.0GL Volvo Penta I/O starting problems sometimes after sitting...?

Any help would be appreciated...I have an 02 Reinell Volvo Penta 5.0 GL (carburetor). Summer time I use this boat at least two times a week. Last summer had some problems when I was cruising and the engine would just cut, turned out to be a wire under the dash so the marine placed fixed it with a new harness, they said it is common on those years...This summer the last about 5/10 times it starts about the second or third time at the dock and we boat out on the lake maybe sit and board some and then it doesnt want to start back up for 15 mins. We run the blower, so shouldnt have vapor lock and I even opened up the back hatch for 5 mins and tried. It cranks over good but doesnt want to stay started. I smell gas...Yesterday we left the dock and boated about 2 mins and sat for 40 mins then it didnt want to start for 15 mins. Got it back on the trailer and I turned it off and I started it right back up first try. The fuel filter and fuel pump got changed last summer. The engine is not hot and shouldnt have bad gas because I have gone through many tanks of gas this summer....any suggestions?

I have a similar problem.

Long cranking time (30-40 seonds) after sitting for a week.

The carb is heating up and the gas inside is boiling off.

The intake manifold has exhaust gas passages to improve cold operating qualities and such.

I have ordered a phenolic carb spacer to insulate the carb from the manifold.

Unfortunately, it has not arrived and I don't know if it will work.

Another option for this condition are intake manifold gaskets with the exhaust gas passages NOT cut out. (this is a much more complicated install than a carb spacer)

My intake manifold has the paint burned off at the base of the carb.( 5.7 GM )

just some thoughts, no answers...

John

1) In warm weather it is normal for the gas in the bowl of the carb to evaporate.
2) Running the (bilge) blower will have minimal impact on vapor lock. The term vapor lock refers to a condition INSIDE the engine (carb) while the bilge blower is designed to deal with gas vapor OUTSIDE the engine.

same thing at the lake again today ran fine all day but for a small glitch it didnt want to start for about 10mins out of about 20 starts today but after that it started fine...It starts for a second then just dies, sounds like it needs gas and it only sat for 5 mins....

Capt. Bob,

On a unrelated note, How is that Lancer with the open exhaust running?

Did you ever get it above 4200 rpms?

Wondering what your top speed is and what it topped out at......

Wondering about my flame arrestor as another factor in performance issues......(high rpm restriction)

John

Kyle,

Wonder if your carb is somehow running too rich....

Culprit could be- choke adjustment?

-Float adjustment of carb?

-Power valve failed, letting in too much fuel all the time?

Fuel pump diaphragm bad, overflowing into carb intake?

What brand of carb/ model do you have?

John

Fuel issues are dangerous on boats as I'm sure you are aware.....

Im not sure of off the top of my head, will have to check it. But when the engine is running it runs great!...So the other day at the lake I was cruising and it totally shut off and had to get towed in again! I guess its one of those damn wires that came loose again, I couldn't find anything loose, so I will have to take in back to the shop again.

duo_prop_dad said:

Capt. Bob,

On a unrelated note, How is that Lancer with the open exhaust running?

Did you ever get it above 4200 rpms?

Wondering what your top speed is and what it topped out at......

Wondering about my flame arrestor as another factor in performance issues......(high rpm restriction)

John

Click to expand...

For much of the summer I had an annoying problem... It would start and idle fine, shift into gear...all OK... Open throttle...stall.
Disconnected linkage at the carb and if I opened the throttle slowly ( in neutral, warmed up)... it would still stall. Replaced accelerator pump same thing.
Eventually got it to run much better by bending the link between the throttle and the accelerator pump lever so that it was tight, i.e. no play when you open the throttle. That and some back problems have kept me off the water most of the summer. On the couple of times we had it out, it ran quite nicely. It will rev over 4200, however, the day we took it out, running at that speed even in a deep V hull, it was more than my back (and wife) could take. Barnegat Bay runs a short steep (3 to 4 ft) chop, often with breaking tops... so speed trials will have to wait for a calmer day.

Was there ever a resolution to this problem? I am having the exact same thing happen to my 2000 5.0 VP and would like to know how to fix it.

Thanks