what would make milky oil on a ms 440/460 hybrid?

[dolmarkid]

curious what would cause milky bar oil

 

[460 magnum]

I had a husky 51 doing the same thing I drained all the oil out and put new in and haven't noticed it since.

 

[dolmarkid]

im hoping its not a leaking case gasket

 

[blsnelling]

They only thing I know that could make oil milky is water in it.

 

[drf256]

Black oily residue all over piston skirt as well. Not excessively smoky exhaust. Bar oil was fresh.

The piston looked scored, but the black marks wiped off piston easily.

Could the case gasket be bad?

 

[huskihl]

I know from past experience that if the gasket is bad at the oil tank, it'll blow white smoke and smell just like burned bar oil. There's no mistaking it. I'd imagine if it was bad outside that it would show up while tuning or a vacuum check.

It could also be air bubbles giving it the milky appearance. But not sure where it would come from.

Maybe possible that the bar oil jug sat in the rain without the lid?

 

[huskihl]

Black oily residue all over piston skirt as well. Not excessively smoky exhaust. Bar oil was fresh.

The piston looked scored, but the black marks wiped off piston easily.

Could the case gasket be bad?

Any chance that the bottom end or crankcase was black inside and your oil is removing it and leaving temporary traces on the piston?

 

[blsnelling]

A bad case gasket is not going to turn your oil milky unless you had it setting in water.

Vac test it and find out.

 

[Chainsaw Jim]

The question is whether or not it happens again after you refill the flushed and cleaned oil tank with fresh clean bar oil.