why is there gas in my oil?

PortlandBrder · Soul Rider Joined: 18 Apr 2004 Posts: 352 City: Portland

I just finished changing my oil on my 89 MC Prostar. I noticed the smell of gas in my oil. I just had the Carb overhauled, had problems with right needles and ended up dumping ALOT of gas in, motor still ran but smoked like crazy. Im no mechainic so could that have anything to do with that? if not what would cause this?

MrBlean · Posted: Jun 03, 2005 10:00 pm Post subject:

If the engine is running excessively rich (too much gas) this washes oil from the cylinder bores and because it is so much thinner, it can "blow" past the rings and into the sump on each compression stroke.

The smoking can also be due to excess fuel and oil being burned off in an inefficient manner (see how much smoke comes off oil if you burn in free air).

Oil diluted with fuel in your crankcase is bad for your engine(poor lubrication). Change the oil filter and start over. Make sure your carb problems are cured first, though.

I'm not saying this is the only possible explanation for your problem but is likely based on the preceeding events.

PortlandBrder · Soul Rider Joined: 18 Apr 2004 Posts: 352 City: Portland

Mrblean, thats kind of what I figured it was. I just wanted a second oppinion. I change the oil tonight, I didnt run it again, I will tomarrow and see how my oil is. Should I be safe and flush it again? I let the oil drain for several hours.

MrBlean · Posted: Jun 04, 2005 5:49 am Post subject:

With the oil diluted by the gas it's viscosity will be low and if you leave to drain overnight (or a few hours) you should get 99% of it out. I wouldn't worry about changing it again but do check it after your next run to make sure the problem doesn't recur and isn't due to a different fault.

Good luck!

PortlandBrder · Soul Rider Joined: 18 Apr 2004 Posts: 352 City: Portland

thanks, I run it today and see if I notice gas.