bud,I have to be honest...I haven't had that problem....the pullstart bolts on tight,so I'm not sure how the oil could get out....oil does manage to seep out the crank,thats how the one way bearings eventually slip in the pull start.....but its contained inside the housing....
try cleaning the motor,and trace it that way..you'd be suprised how oil travels around a motor while running.....look at the front bearing...and keep an eye on the exhaust gasket,like the guys said..
also,if the engine is really running rich at break in settings,the cv's can leak quite a bit of fuel out of the front bearing..
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