Volvo Penta 5.0gl only runs with throttle cranked way up

[j6allen]

My Volvo penta 5.0gl (carburated) began running rough last week, I replaced 2 plugs that looked fouled, a week later the first time taking the boat out it wont run unless I crank the RPM's up to 4k and it still runs rough and smokes white and there was alittle water discoloration by the stern drive. I checked all the plugs and wires and I'm getting spark and the firing order is right but I was able to remove plug wires from 4 specific cylinders and it made no difference to how it ran (they were not the ones with the new plugs) there seemed to be some gas leaking onto the intake manafold as well, I could not determine were it was coming from. Any help would be greatly appreciated

 

[CharlieB]

Re: Volvo Penta 5.0gl only runs with throttle cranked way up

First, you need to be sure that your carb is not flooding, leaking gas on the intake can be a very dangerous situation that MUST BE rectified immediately.

Hopefully flooding is your only problem causing spark lugs to foul.

Which 4 plugs where fouled and what did they look like?

If it was the two inside plugs on each side of the motor then You could have Head gasket issues. Do not start taking anything apart until you have looked and tested. The white 'cloud' could be water or it could be fuel flooding.

One thing at a time, deal with leaking fuel first, then repost if problems persist.

 

[Bondo]

Re: Volvo Penta 5.0gl only runs with throttle cranked way up

Ayuh,....

At Best,.. You need to Rebuild the Carb,.... Possibly Replace it...

 

[j6allen]

Re: Volvo Penta 5.0gl only runs with throttle cranked way up

Well as it turns out, it did need a carb rebuild. The float had ruptured.

Thanks for the help.