2003 Mercury XR6 150HP losing oil from engine mounted oil tank between uses

[tom1949]

I have a 2003 XR6 that keeps losing oil between uses.  Last year I thought I had it fixed when I replaced the squeeze bulb.  At that time it would not start and the screw on fuel filter had oil in it.  This year the first time out it wouldn't fire and the engine mounted oil tank is now half full and I have oil getting into the screw on fuel filter again.  Is there a check valve in the primer bulb to keep fluids from going back into the fuel tank?  Any ideas why oil leaks down?  Thank you in advance.
Tom1949

[D.W. Verts]

You do have a PRIMARY oil tank too, right? I'm out of practice at this but you should have two tanks. And yes, the primer bulb has a check valve, but oil shouldn't be able to leak back into the fuel tank from the reserve oil reservoir.  Like I said, it's been a while (and one stroke) since I messed with these things.

Dale

[tom1949]

Hi, Thanks for the reply.  Yes I have a 3 gallon tank in the bilge and a smaller tank on the engine itself.  I ordered a genuine Mercury primer bulb to replace the 1 yr old walmart bulb and see if that fixes it.  Hopefully