Leaking MS390

[Engineer]

Been having a nagging problem with my MS390.  It leaks bar oil on the floor.   I found a puddle of the stuff on my brand new concrete slab last fall ( >:( ) and since putting a piece of cardboard under the saw it has saturated the cardboard.  It leaks whether or not the saw is vertical or horizontal, and the cap is tight.

Any suggestions on how to get it to stop leaking?

EDIT:  I bet I figured it out.  I've been using winter weight oil, and the oiler is maxed out.    It leaks all the time, though; not just after use.    Not a big puddle - the saw's been sitting unused since probably October, so maybe an ounce of oil has leaked out.

[sawguy21]

If that is a two piece tank, which I believe it is, the o-ring seal is probably leaking. We had a new saw do that right out of the box. The seal had not been installed :

[treeape]

             how big was the puddle? i own about 16 saw's plus the 8 my boss gives me to use. just about everyone will leave a little oil behind if it sits on the floor for a bit.  before you put it away open the oil cap to relieve any preasure then tighten it before you store it.

         

[Pullinchips]

My ms390 leaks like the previous poster said. Not excessive but normal.  This is also due to the oil that remains on the chain bar and in the bar grove, this leaks on to the surface that you are storing it on.  I would think that if the leak stain is more that a couple of inches you have more than just the normal amout of lube leaking off of the bar and chain.

-nate