fuel and oil leak?

Discussion in 'Motorized Bicycle Trouble Shooting' started by graydog8josh, Apr 1, 2013.

  1. graydog8josh

    graydog8josh New Member

    Nov 23, 2012
    Likes Received:
    My bike is leaking out fuel and it is leaking oil from the bottom of the crank case
    these are two separate problems.
    the fuel i can't tell where its coming from but its over some of the cooling fins, there's some unburnt fuel especially after i run the engine hard. its all the way around the the fins on the cylinder and on the seam where the case gasket is.
    the oil is seeping out of the the bottom of the crank case, its pretty consistant that after i run the engine there will be a hanging drop of oil on the screw at the bottom of the crank case. I dont have any idling problems, and the engine seems to run fine, what is going on here?
  2. crassius

    crassius Well-Known Member

    Sep 30, 2012
    Likes Received:
    first clean it well (gas or wd40 on a rag & poke it between fins with a screwdriver)

    then run it a bit and see where oil shows up (probably around exhaust gasket or head gasket) - tighten appropriately

    also, always turn off the fuel when you park the bike
  3. 2door

    2door Moderator
    Staff Member

    Sep 15, 2008
    Likes Received:
    Exhaust manifold gasket? Head gasket? Spark plug? Cylinder to base gasket?

    Some instructions that come with the kit tell you to "finger tighten the spark plug". If you don't tighten it more than that it will leak.

    Like Crassius said, clean the engine well and ride it for a short distance. Look for a source. My feeling is that the leak is above and running down to the bottom of the case.

    Let us know what you find.


Share This Page