Puff,...
When a float sticks,.. the engine floods.... eventually, gravity leads this fuel downward into the crankcase... which increases the volume to the point of spitting it out the crankcase vent tube... into the airbox...
This is how a fuel leak makes an oily, gas mess in the airbox...
Once you fix the cause... you need to clean out the airbox and filter,... and if it was bad enough (too much fuel to evaporate)... you'll need to change the oil...
I should have mentioned the need to change the oil...
It will, mostly evaporate.... if not from sitting, once the heat of running happens... but, it's best to get clean oil in there...
Us oldsters have explained these things many times,... and we, meaning I, can get lazy.... and leave parts out...
That is why I appreciate comments from fresh voices...
Anyway... the problem is in the floatbowl... either floats are sticking or float needle is leaking...
Once you fix it... it would be safe to change the oil... as it is most likely contaminated by the leaking fuel...
I know it's nasty news....and a PIA... but, these things can happen to any carbed engine...
Good news is,... you caught it...
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