Oil Leak on Harley

By Dennis Santopietro

Q: I have 89 FXRS I guess it`s a bottom breather, I just bought an ultra lower set of cases. I had the crank & rods installed, I installed a set of 3&5/8 jugs & pistons, S&S heads top breather! Now I have oil blowing all over the engine?I need some DVD to help me solve this???? can you help me with this oil leak on Harley? Dennis D.

A: Dennis, It sounds like you have a lot going on here. I am assuming that the oil is blowing out of your top breather bolts. The cases would need to be bottom breathing. Are they? Also, were the heads new or used? If they were used, do you have any idea what condition they were in? Check to see if the timing mark on your breather gear is correctly aligned with the correct cam gear timing mark. Also, you can pull your rocker boxes to check your umbrella valves. They should be on the intake side. If you are in your cam compartment, be sure your oil pump is working correctly. Check the condition of your pinion gear. These are just a few things that come to mind. Good luck

Videos: Cam Class

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10 Responses to “Oil Leak on Harley”

  1. ROBERT

    Make sure you have the air/oil separator in place-inside the tube inside of the nose cone is where it goes. ALSO-vital to have the CORRECT nose cone gasket ! Ask me how I know. Had the same issue when I put the EV27 in, even being careful.

  2. Darryl Lee

    I have 79 low rider FXS, after sitting for awhile it throws up oil through breather tube while kick starting. Back in the day everyone would run breather tube down to the bottom between engine and transmission.

  3. Ricky Jamison

    I have a Electra limited 103 engine and I am a little oil from my breather. Do you have any idea of what is causing this?

  4. Daniel Morgan

    I know it’s not emissions legal but vent those heads to atmosphere instead of your breather. When you squeeze out the bore with a sidewinder this can be a problem. You might even want to run two separate breather hoses.

  5. Karl

    I have some oil leaking around my rocker box covers. I need to take the heads off or the motor out to replace these gaskets? 1981 superglide stock

  6. DAN

    2001 road king sat over winter oil leaking from rear wheel

  7. bob burnett

    my 2003 xlh leaking primary fluid when on kick stand..I have recently put on forward controls..Hope that didnt cause it,,dont see how it could.

  8. Duane Mitchell

    I too have a leak but it's on my 2006 roadking classic . On the bottle of the primary crankcase after a stater and voltage regulator change

  9. Dennis Wells

    My 2005 Harley Ultra classic leaks transmission fluid when its on its side. I am old and let it lay down while sitting at a stop light. Not on purpose. before I could get it up, tranny fluid was pouring out the side cover

  10. Allen

    Sounds like my FXRS-SP and that nasty idea of a check valve that never works on 1990 models? Let it sit and it pumps oil out of breather pipe or in your case up to the air cleaner?