Under heavy load......

Discussion in 'Engine, Fuel and Exhaust' started by 89stroker, May 11, 2013.

  1. 89stroker

    89stroker Active Member

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    I have something I want to ask the experts on this site: On my 99 softail, stock EVO other than aftermarket air breather, mufflers and cam. When you ride it hard for extended periods, it pukes oil out the breather and covers the right side of the bike from the air cleaner back. It is fine when you ride normally, runs good, doesn't use oil, approx. 30,000 miles on the clock. I have had this bike for 2 years and it has done this to me twice, once last year when I was late to meet up with my buddies to go on our annual 600 mile run, I was late to meet them so I rode it at 90+ for 2 hours to meet up with them. Then it happened again yesterday, I am moving so I was pulling my loaded down trailer against a 40+ mile per hour corner wind for about an hour and it puked oil all over the right side from the breather again. Only difference in the bike this year from last is that I installed an EV27 cam, new lifters and adjustable push rods over the winter.

    I want to summon some of the experts as to what may be happening. One thing comes to my mind is maybe the umbrella valves need to be replaced. Any other ideas?
     
  2. HDDon

    HDDon Experienced Member Contributor Retired Moderators

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    I think the umbrella valves would be a good place to start. I have a 94FLSTC with the same set up, and when pushed hard it use to do the same thing. I bought a cross over pipe that connects the two breather holes and I ran a small rubber hose down to the bottom of the frame. I put a small fuel filter on the end of the hose to catch the oil and when I change oil I also change the small filter. No more oil down the right side of the bike.
     
  3. 89stroker

    89stroker Active Member

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    I have a set of new umbrellas so when I get time I will replace them. also good idea about tieing the breathers together and then down to a filter. I think I have most everything I need to do that, including the filter.

    Thanks.
     
  4. Jack Klarich

    Jack Klarich Expert Member

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    Seems to me there was a fix for this by enlarging the oil return holes in the heads for one, plus you can change the breather timing and or window to relieve the pressures thus by creating faster oil return also
     
  5. 89stroker

    89stroker Active Member

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    Thanks Jack, seems to me I've read that somewhere also. I'll do some research to those things you mentioned.
     
  6. Hoople

    Hoople Account Removed

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    I would also perform a cylinder leakage check. Since riding hard makes it worse, bet you find blow-by past the rings more than 10%. You will hear and even feel the air coming out at the oil filler neck.