Airhead Rear Main Seal

Discussion in 'Airheads' started by TimTowtdi, Dec 27, 2009.

  1. TimTowtdi

    TimTowtdi Been here awhile

    Joined:
    Nov 6, 2006
    Oddometer:
    241
    Location:
    Middle of TN
    I have the rear main installation tool jtwind sells. In the instructions he mentions two different depths for the seal to be installed to. It is differentiated by whether or not the block is machined in the area of the main seal.

    I just installed a new seal on a 76 R90 and used the deeper setting because when I tried the setting for a block that has not been machined, the seal rubbed on the flywheel.

    What were the year breaks for the later and earlier seal depths? Does anyone have pictures of both? Jtwind?

    Tim
    #1
  2. Infracaninophile

    Infracaninophile Finding My Way..

    Joined:
    Sep 27, 2001
    Oddometer:
    7,535
    Location:
    Rhode Island, USA
    :ear

    Tim: Am going to do mine this week so I am all ears to hear what you learn.

    Tom
    #2
  3. jtwind

    jtwind Wisconsin Airhead

    Joined:
    Nov 19, 2004
    Oddometer:
    3,474
    Location:
    Madison WI
    I've never known where the year break is either. I tell folks that when it doubt put it in at the shallower setting and if it isn't deep enough it will be obvious and you can set it deeper. Alway helps to make note of how deep the original was in also.
    #3
  4. TimTowtdi

    TimTowtdi Been here awhile

    Joined:
    Nov 6, 2006
    Oddometer:
    241
    Location:
    Middle of TN
    Ok. Thanks. I am thinking it is somewhere around 1975 or earlier. Probably a pre 1976 thing. I found this page by and he has a note in it about that being only for the older seals according to Oak. I wll look into that.

    Tim
    #4