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I too have discovered a large amount of fuel in my crank case. I was having a high speed problem - it operated well at low speed and idle - I pulled the carb to check and found it clean. I re assembled, and found the fuel line bulb would not get hard and expect I was pumping into the crankcase....??? Is this a fuel pump issue?
I don't comment on small outboards (9.9's)because I don't service enough of them but, I was on a service call on a Honda BF30 with 5400 hours on it. The owner installed a new portable fuel tank, and developed a rod knock due to gas in the crank case.
Here is what I found, maybe this will help....... The new portable fuel tank is un-vented and requires a fuel demand valve, he did not have one. With the tank hooked to the engine and the sun beating down on the the tank, it swelled like a balloon and pressurized the fuel system forcing fuel past the carb float needles and into the intake past the rings and into the crank case.