Crankcase overfull

[Old Crow]

Checking the oil in my 2004 Yamaha F115TLRC I found the oil level overfull.
The oil looks OK but also seems much more lighter than is should.
I can see the oil in the dipstick tube and when I shack the motor I see the oil slosh around
Do I have fuel contamination?

 

[Old Crow]

Re: Crankcase overfull

Pulled the plugs, they look fine
Pulled fuel pump and pumped up primer bulb as much as I could, see nothing dripping form pump.
Also pulled injector rail, nothing dripping from injectors

 

[Woodnaut]

Re: Crankcase overfull

I over-propped my F90 once and it produced a "making oil" situation. I re-propped so that WOT was 5,900-6,000 RPM and haven't had a problem since. What is your RPM at wide open throttle?

 

[99yam40]

Re: Crankcase overfull

over propped or running too cool is my 1st thoughts
If it is fuel contamination then you are running it with less lubrication than it should be.
Change the oil and then fix the problem

 

[Woodnaut]

Re: Crankcase overfull

Isn't the the (low pressure) fuel pump located on the back of these engines? It seems I read that a leaking diaphragm could also permit fuel to enter the crankcase.

 

[99yam40]

Re: Crankcase overfull

Isn't the the (low pressure) fuel pump located on the back of these engines? It seems I read that a leaking diaphragm could also permit fuel to enter the crankcase.

He said he checked that

 

[Old Crow]

Re: Crankcase overfull

I'm running 59-6100 rpm's

I have changed the oil, oil filter, reinstalled the recommened amount of oil; now I'll watch to see if I again "make oil"

I see there is a upgraded thermostate (hotter), I'll look into that