My 15hp has gas in the crank case oil!

[Wolf pack]

I have a 1997 15Hp 4 stoke, I have discovered that when I checked the oil in the crankcase the oil had a strong oder of gas. The oil was thin after I drained it. I checked the fuel pump diaphragm and that seem fine.
The outboard was stored for the winter and has not run in 7 months. Was not fogged either.

Has anyone had gas in their crankcase oil? I'm stumped & boggled!

Thanks!

 

[boobie]

Re: My 15hp has gas in the crank case oil!

In what position was the mtr stored ??

 

[Silvertip]

Re: My 15hp has gas in the crank case oil!

It may have had gas in the oil before you stored it. Lugging a four stroke due to running a prop with too much pitch is a good way for an engine to "make oil". And you should be checking oil much more frequently than you apparently are. Oil that is thinned with fuel will not lubricate well. You don't want to know what the repair cost would be to rebuild the engine.

 

[boobie]

Re: My 15hp has gas in the crank case oil!

Another thing I just thought of. Is the mtr running to cold ?? Bad thermostat ??

 

[F_R]

Re: My 15hp has gas in the crank case oil!

That ususally is the result of a leaking fuel pump diaphragm. Are you sure it is "fine"? A pin hole will do it.

 

[Captain Caveman]

Re: My 15hp has gas in the crank case oil!

I checked the fuel pump diaphragm and that seem fine

How did you check it? How do you know that it's fine? Replacing the diaphragm would be a good thing to replace no matter what.

 

[Wolf pack]

Re: My 15hp has gas in the crank case oil!

My motor was stored in an upright position, well actually i never took it off the boat. I use the outboard as a kicker! When I removed the fuel pump there was 1 odd thing I noticed. There was a small spring on the screw thats hold on the diagram and a loose small retaining type of washer. I did notice that there was another one of these small spring & retaining washer that was in a small hole on the housing
that covers the diaphragm. These small holes are in the corner of the housing and there are 2 of them. I put the spring back in empty hole and put the retaining washer over it. I have looked online for a diagram, but only shows the housing, not whats inside of it.

In addition I had to order a water pump kit, because no water was coming out the pee hole, turned out the impeller was toast. Once thats gets installed I will try to start the outboard.
Hopefully!