Darn it

Discussion in 'Engine, Fuel and Exhaust' started by Adamal47, Mar 10, 2012.

  1. Adamal47

    Adamal47 Active Member

    Took the bike out for a quick 10 mile ride yesterday. Parked for about 30 minutes and when I went to get back on the bike I noticed a small puddle of oil on the ground. Thanks to previous posts on the forum I was able to narrow the location down to either the 2nd rocker box gasket or comming out of the middle of rocker box( I forget what that part is called). Question is if it is comming out of the middle part that's because there is too much oil in the bike. Is this correct to assume or what else would cause it?
  2. Breeze3at

    Breeze3at Well-Known Member

    I've always just referred to them as top/middle/bottom rocker box. Evo's were noted for leaks in the rocker boxes, especially at the front left and rear left. Too much oil is not usually the reason they leak. They are pretty skinny there and heat/cool cycles just degrade the material and they leak, usually from the middle spacer. You need to replace at least the top 2 gaskets. The gasket between bottom box and head does not usually leak.
  3. HDDon

    HDDon Experienced Member Contributor Retired Moderators

    Have you checked to see if the rocker box screws are tight?
  4. Adamal47

    Adamal47 Active Member

    I didn't want to touch the screws just yet because I know they are very picky with the torque settings on those. What about the breather in the middle of the rocker box? I thought the oil was comming from the gasket but I noticed there is oil splatter inside the openings of the rocker box.
  5. Jack Klarich

    Jack Klarich Guest

    Change the rocker gaskets, this is the only way to be sure of NO leaks. Observe the un torquing sequence so as to not warp them, try Cosmetic gaskets and warm the engine up before each ride, this is the main reason Evos leak
  6. STEVE07

    STEVE07 Well-Known Member Staff Member Super Moderators

    After sitting for the winter my Evo leaks from the rocker boxes for the first few rides,then it quits leaking for the rest of the year.
  7. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

    Another worry with the EVOs is the middle rocker box build up can have a hairline crack and leak when hot. Inspect it carefully to see if there is anything visible. You may have to do a penetrating dye (or black light) type inspection to see the crack when the engine is not hot.

    Also, if the top rocker cover is hit with cold water when hot, it can warp and then will not seal well. You may have to disassemble the rocker box cover and check the top cover for flatness. Good time to check the middle one for a crack.

  8. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    In the past i have had on 2 bikes the lower rocker gasket fail this was on the front left on one and close to the breather on the other both on the front cylinder
    Both bikes had been assembled with a 2 part paper lower rocker cover gasket and the gasket kit came with a 1 part metal gasket and the paper gasket had failed and it was a wee bit of a pest to get the paper gasket off however the metal one seems to be much better
    The excess oil in the air cleaner could be caused by bad umbrella valves these are located in the middle part of the rocker cover
    Having a wee bit of previous experience with evo rocker boxes if i were in your position i would get a rocker box gasket kit and replace them all the harley kit also contains the umbrella valves

  9. 01 rk

    01 rk Active Member

    It is important that the lifters go back where they came from,ie: front exhaust, rear exhaust etc. The result of not going back correctly could be a lifter failure. Each one wears differently. The best thing to do if you don't know is check the tappet blocks for tolerence, if ok then replace the lifters. If the blocks are out replace them as well, even a 1/2 of a thousand extra clearance will cause a lifter to float. I found out the hard way many years ago.
  10. dbmg

    dbmg Guest

    That would be my thought. Try riding longer and see what happens...:s