Engine running cold will not cause gas to get in the oil. Not sure how you
determined you have gas in the oil but when it happens it is usually stuck
carb float. Or a cylinder not firing at all.

"Mr Ranger" wrote in message
...
Gas in my oil. Boat runs perfect. First, thinking it can't be the float
since boat runs great. Changed the fuel pump thinking must be problem.
Still gas in oil. A friend ran into a mechanic who suggested it had to be
the Thermostat. Said the boat is not getting up to operating temp, the
gas
is not being burned in cold engine. Sure enough, my thermostat was not
working. Tried to install thermostat, however could not figure out how to
remove stat out of housing. I have a Merc design #1 SB housing. Could
not
get stat out of housing, so I punched out middle so water could pass
unobstucted and installed the thermostat in the top of the engine where it
normally goes. Now boat is running at proper temp, however I am still
getting gas in the oil. Now I am wondering if the position of the
thermostat may be important enough to make a difference? Any Ideas or
suggestions? I am running in the straits of Mackinaw, from early spring
until ice forms.

Thanks, Mr Ranger