have a 90' softail custom with a s&s carb....breather tube from crankcase is attached tocarb body....keeps sucking oil from crank into carb....any ideas ? have already performeda sealing process at the intake manifold......?
querie says it all
Welcome. Thank you for choosing Just Answer.what "sealing process at the intake manifold" did you perform? please be specific.does this happen only after the bike has been parked for extended periods?tell me everything you can.Steve
have replaced the seals w/original hd parts...then
your problem is a common one known as "sumping".this is caused by oil from the tank gravity feeding into the engine through a check ball in the oil pump.when the engine is started, the breather does what is suppose to do and expels excess oil from the engine.the official HD fix is to add a length of oil line to the breather hose and stick it into the oil tank before starting the engine, after an extended park.this is also why it is important to never top off the oil in a Harley until after running the engine to operating temperature. sometimes, you can sump a quart or so and the engine will pump it back into the oil tank with no problem, but if the oil tank is topped off first, it has no place to go and again, the breather gets rid of it.the oil tank should never be more than 3/4 full when the oil is hot.the only solutions to the sumping issue are, don't park the bike for extended periods (not always an option), try to lap the check ball seat using an old EVO pushrod, the replacing the ball and spring with new or replacing the oil pump.let me know if you need more help.Steve
how do i lap check ball seat...? thnx
it is not difficult, but it is labor intensive:- remove the oil pump body from the engine.- remove the check ball cap, spring and check ball. discard the ball and spring.- clean the oil pump body with brake cleaner and compressed air.- apply lapping compound to the ball end of a used EVO pushrod.- lap the seat until it appears smooth.- thoroughly clean the lapping compound from the oil pump body. remove all traces.- assemble the oil pump on the engine.- install a replacement check ball and spring.some people have had good luck with this technique, others have not. it is not guaranteed to solve your problem.let me know if you need more help.Steve
30+YRs,MMI,HD tech,HD early,engine rebuild/perf,bike builder,kit bike program manager, cci 2001-2004