Excessive engine oil

[PioneerSC110]

I have an 06 f250 thats been sitting up for approximately six months now. Took the cowling off the other day to start my services and checked the oil level before draining. It was all the way up the dipstick , almost Two inches from the yellow handle. The motor was trimmed level also. I drained the oil and changed oil filter and refilled with oil.(5.9 quarts). Went on a test run an day later and everything seemed fine, 4-6 hrs. Today I removed the cowling and checked the oil and the same thing has occured again. Way too much oil. It is all the way up the dipstick again. I know i drained every bit of oil out, but this has me puzzled. Couldnt be water because it isnt milky colored. Gas?

[boats.net]

May be gas, check to see if smells like gas. May have float valve in vapor separator tank sticking open.

[Hollowman]

If it sat for a long time before you checked the oil,it will look overfilled. The dipstick levels are actually only accurate when the oil filter is filled with oil. The filters have an anti drainback valve but they are crappy,and over time,when just sitting, the oil in the filter will drain back into the crankcase causing the dipstick to look high.

The best way to check the oil level is run the motor for a few minutes (on the muffs of course),shut it off, wait 3-5 minutes then check dipstick. If you were sure you filled with the correct amount to begin with,You will probably find the level right where it should be.

If you doubt these filters anti drainbacks are no good,next time you do an oil change, do it after the boat has been sitting idle a few days. When you spin off the old filter,nearly zero oil will drop out of the filter. Makes for a cleaner process compared to spinning it off after just running it,which will be very messy,as the filter will be full,(which actually is how you should do it,because its better to drain your oil when hot.)

[PioneerSC110]

Thanks for the info guys. My boats at the dealer so hopefully he can determine the cause.