HELP! Gas in the lubicating oil

[chris45]

Hi guys. A bunch of us are finding the oil in our outboards is getting contaminated with gas. We all run on regular gas. It might be a coincidence but the only two in our group not affected so far run on super grade gas. The engines are mainly 50s running flats skiffs.
Any ideas anybody?
Thanks
Chris

 

[DMSOUTH]

Re: HELP! Gas in the lubicating oil

4 Stroke I assume?

 

[chris45]

Re: HELP! Gas in the lubicating oil

yes, 4 stroke! When we take out the dipstick to check oil level it is clear that the oil is contaminated by gas.

 

[DMSOUTH]

Re: HELP! Gas in the lubicating oil

Do a search on this forum--many posts about 4 strokes "making oil". Quite often due to being over propped...

 

[Silvertip]

Re: HELP! Gas in the lubicating oil

And too much idling or slow speed operation. Run the be-jeepers out of it.

 

[chris45]

Re: HELP! Gas in the lubicating oil

I did a search and yes it seems a lot of people have this symptom, and usually it appears to be either the thermostat or the diaphragm is faulty.
However,because this has happened to several boats at once (all in daily use, all running at speed ie not trolling)I was wondering if it might be the gas, common to every boat that has this problem, which down here is not reliable. is there any possibility that (say) reduced octane level might cause this?

 

[robert graham]

Re: HELP! Gas in the lubicating oil

This is a fairly common 4 stroke issue, nothing to do with octane of fuel. Good Luck!

 

[Woodnaut]

Re: HELP! Gas in the lubicating oil

Guys - not meaning to stir up the ethanol thing here (again), but for years and years many gasoline merchants have cut their gas with ethanol to "stretch their profits" so to speak. A few years ago some testing of gasoline here in the Houston area revealed that some gasolines were as high as 48% ethanol (which is absolutely ridiculous). I was just wondering if the local marina might have gotten a batch of gas that was on the really high end of the ethanol spectrum thereby causing fuel pump diaphragm damage in several engines. Just a thought.....