fuel in the oil

bertos

Cadet
Joined
Jul 5, 2007
Messages
24
i have a 72 sea ray with a 350 chevy omc outdrive i was getting smoke when i took for a ride.I changed my oil because it was do anyway, and it had a gas smell to it. well i took it out for another run it ran good but notice the oil was higher on the dipstick than when i check it the day before.The carb was rebuilt last year.so any idea what else it could be.thanks for the help.
 

bhammer

Ensign
Joined
Mar 29, 2008
Messages
963
Re: fuel in the oil

I can' help you, but would say that I would not run it anymore until you get the issue fixed or you will be coming back saying your engine went kaboom.:mad: But, I am sure you know this....

Search the threads, I remember seeing a thread with a similar problem but don;t know what the casue / fix was.
 

Maclin

Admiral
Joined
May 27, 2007
Messages
6,761
Re: fuel in the oil

A non-Marine mechanical fuel pump can pump gasoline into the crankcase if the diaphragm is compromised.

Some carbs have plugs in their bases that can start leaking fuel right from the fuel bowl into the intake manifold.

Some carbs have a rubber diaphragmed power valve that if ruptured will leak right from the fuel bowl into the intake manifold.

In either of the last two scenarios the entire fuel bowl can drain this way, any residual pressure from the fuel pump can let even more fuel get into the carb as it drains. The fuel can work it's way past the rings into the crankcase.

If it is one of the last two scenarios then while trying to run the engine the engine will flood and run very poorly if at all at idle, will be hard to start and will foul the spark plugs.
 

danfrompgh

Petty Officer 3rd Class
Joined
Jul 8, 2007
Messages
76
Re: fuel in the oil

Not an expert on the carb posibilities but GM 350"s were notorious for the fuel pump going bad and filling the crankase up with gas. This is assuming it is the mechanical pump,right?
 

bertos

Cadet
Joined
Jul 5, 2007
Messages
24
Re: fuel in the oil

yes it is a mechanical fuel pump.Thanks for the help it getting look at tomorrow thanks again

rob
 
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