2002 Mercury 90hp 4-Stroke (YamaMerc) making oil while not in use???

[Jeepcollector91]

I currently have a 2002 Mercury 90hp four stroke outboard. When I purchased the boat, motor, and trailer the oil level was good. After hauling the boat over 300 miles home I planned to take the boat out on a test run the next day so I checked the oil again and it was way over full with the strong smell of fuel. Seemed that the fuel tank over pressurized while in transit forcing fuel into the crankcase either thru the carbs or thru the fuel pump. The spark plugs were dry so I removed the fuel pump to check it for a leak. Fuel was indeed leaking past the fuel pump. I installed a new fuel pump, cleaned the fuel tank vent and installed a fuel demand valve in the fuel line. Took the boat on a 40+ mile test run and all was good. After returning home I checked the oil level again and it was perfect with no smell of fuel. The boat then sat unused for a few months. Now after refurbishing the trailer and installing a new fish/depth finder I am finally ready to use the boat this season. Checked the oil today and once again it is over full with fuel contaminated oil. Is this a common issue with these engines? I'm assuming stuck float but with the fuel demand valve limiting the fuel supply I wouldn't expect that much fuel in the oil.
Any info would be greatly appreciated. I searched for other threads on this topic but only found info on these engines "making oil" while in use. Not while in storage...
Thanks.

 

[GA_Boater]

Are you disconnecting the fuel hose from the motor?

 

[Jeepcollector91]

Are you disconnecting the fuel hose from the motor?

No. Currently doesn't have fuel line disconnects. All I did was add that fuel demand valve which was supposed to automatically cut off the fuel supply until it has a pull from the engine side. First time I've ever used one. Normally I just install a manual fuel shut off valve.