1983 AQ125A Volvo Penta Engine, Fuel in oil

[BuddhaBelly]

I have a Volvo Penta AQ125A engine that some how gas is getting into the crank case. I changed the oil and filter and ran it at running speed for about 2 hours. When I got back to the dock, once again a large amount of fuel was in my oil. I did a compression check #1 cylinder is 155 PSI dry,170 PSI wet #2 cylinder is 155 PSI dry, 175 PSI wet #3 cylinder is 145 PSI dry and 160 PSI wet #4 cylinder is 150 PSI dry, 160 Wet. I thought maybe I had blown the head basket on one of the oil ports. But these compression numbers look good to me. Any Ideas out there? Any help would be greatly appreciated.

 

[BuddhaBelly]

Anyone have an idea on what is going on?

 

[Maclin]

IN GENERAL on typical internal combustion gasoline engines of that vintage, fuel into the crankcase at speed, assuming it is running well and not flooding out REALLY bad, usually comes from a compromised mechanical fuel pump that is attached to the block and powered by the cam belt or lobe. The inside of the pump can leak fuel under pressure directly into the crankcase via compromised rubber diaphragms. Fuel leaking through the cylinders into the crankcase has to get past the rings and is a slow go. Massive amounts of fuel into the cankcase over a relatively short time is more than likely from a block mounted fuel pump in need of replacement.

 

[BuddhaBelly]

Thanks Maclin,
That is what I was thinking. Pretty much the only think I could think of other than a blown head gasket on the oil port. Thanks again for the help.