Motorcycle Repair: OIL SOUMPING, vent tube, oil tank

Question
MIKE MY QUESTION IS MY 1975 SHOVEL STARTED BLOWING OIL OUT THE CRANK VENT TUBE WHEN YOU SHOUT IT OFF IT POORES OUT WHAT CAN CAUSE THIS TO HAPPEN MY PARTNER CHANGEED HIS OIL YESTERDAY AFTERTNOON THEN THIS HAPPEND I HAD A OLD PAN THAT USED TO FILL THE CRANK CASES AND DO THIS I THOUGHT SHOVEL HEADS DID NOT DO THIS ENY WAY IS THERE ENY THING I CAN DO TO FIX THIS FROM HAPPING  THANK YOU JEFF

Answer
Harleys have had this problem for a long time. It is even a problem in the EVO motors. What you have is a oil tank that is sitting higher than the motor. In order to keep oil from flowing into the motor there needs to be somthing in the oil pump to stop it when the motor isn't running. What they used is a ball help by a spring. Over time the ball and seat get some carbon on it from the oil and slightly sticks open, letting oil weep into the bottom end. When you start the bike, the oil pump can't pump the oil out fast enough and it comes out the vent tube. It doesnt hurt anything, just makes a mess. An easy repair is to remove the spring from top of the oil pump, insert a punch or drift against the ball and give it a tap with a hammer. This will reseat is. remove the ball with a magnet and check it to make sure there is no carbon stuck to it. If its in bad shape replace it. Put it back together and you should be ok.
Good luck and happy riding
Mike