Distributor shaft seal seepage: any tips for getting a tighter seal? | FerrariChat
Buy

Distributor shaft seal seepage: any tips for getting a tighter seal?

Discussion in 'Technical Q&A' started by ztarum, Jan 11, 2011.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. ztarum

    ztarum Formula 3

    Mar 30, 2008
    1,302
    South Jersey, USA
    #1 ztarum, Jan 11, 2011
    The front bank distributor shaft seal is weeping on my 308 QV. Not a lot (no oil on the floor), but oil in the cap and a few drips onto the coolant line below. The seal was installed at the beginning of the driving season and has about 2000 miles worth of run time on it. I pulled the seal (still in the housing), and it looks perfect. No rips, tears or folds.

    When I feel the cam where the seal engages, it is smooth but there is definitely a groove that I can detect with my fingernail where the seal probably rides.

    Is there anything I can do here to improve the situation? Hit with some fine emery cloth maybe?
     
  2. 2NA

    2NA F1 World Champ
    Consultant Owner Professional Ferrari Technician

    Dec 29, 2006
    18,221
    Twin Cities
    Full Name:
    Tim Keseluk
    #2 2NA, Jan 12, 2011
    Try installing a new seal either deeper or shallower so that the lip doesn't ride in the groove.
     
  3. 350HPMondial

    350HPMondial F1 Veteran
    Silver Subscribed

    Feb 1, 2002
    5,336
    18 mi from the surf,, close to Pismo, CA
    Full Name:
    Edwardo
    #3 350HPMondial, Jan 12, 2011
    Grease it up inside real good with,
    Black Moly Grease.
    Before you install it.

    My seals NEVER leak.

    Edwardo
     
  4. Brian Harper

    Brian Harper F1 Rookie
    Owner Silver Subscribed

    Feb 17, 2006
    4,078
    San Jose area
    Full Name:
    Brian Harper
    #4 Brian Harper, Jan 12, 2011
    There are spacers that bearing shops sell for just this purpose. They go behind the seal to make it ride in a slightly different spot. You could also probably just buy a seal that has a very slightly different depth to get the same result.
     
  5. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    #5 Mark 328, Jan 13, 2011
    Last edited by a moderator: Sep 7, 2017
    I am in agreement with all of those comments: shimming the seal, Moly lube, and polishing the shaft with 320 grit sandpaper but I would also use a thin piece (.010") of steel shim stock to help the seal lip over the edge of the cam shaft. In many cases the seal gets damaged on installation. See attached pictures.

    Mark
    Image Unavailable, Please Login
    Image Unavailable, Please Login
     
  6. Buxton

    Buxton Formula Junior

    Oct 31, 2010
    484
    Full Name:
    B Buxton
    #6 Buxton, Jan 14, 2011
    Nice tip, Thank you
     
  7. stevel48

    stevel48 Formula 3

    Jan 4, 2005
    1,998
    Metrowest MA
    Full Name:
    Steve (85 308 Owner)
    #7 stevel48, Jan 14, 2011
    Anyone know the space size?
     
  8. fastradio

    fastradio F1 Rookie
    BANNED Professional Ferrari Technician

    Apr 26, 2006
    3,664
    New England
    Full Name:
    David Feinberg
    #8 fastradio, Jan 14, 2011
    Yep..we manufacture them for the 308QVs, when there's excessive wear on the cam drive.
     
  9. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
    37,288
    Cowboy Capitol of the World
    Full Name:
    Brian Crall
    #9 Rifledriver, Jan 14, 2011
    That was a problem on the 3.2 motor but the drive was a different design and did not catch seals on the 3.0
     
  10. PV Dirk

    PV Dirk F1 Veteran

    Jul 26, 2009
    5,401
    Ahwatukee, AZ
    #10 PV Dirk, Jan 14, 2011
    I ran against that wall on my 3.2, I lubed everything up real well and had a friend rotate the engine from crank pulley while I dropped it in place. Went nicely with cam turning slowly. Slow easy pressure.
     
  11. ztarum

    ztarum Formula 3

    Mar 30, 2008
    1,302
    South Jersey, USA
    #11 ztarum, Jan 15, 2011
    Thanks for all the input.

    I didn't have any trouble getting the seal slid on last time, so I think I'll be OK there.

    Shimming the seal out sounds like a good idea. For those who have done it, how for out from its original seating position do you shim it?
     
  12. Brian Harper

    Brian Harper F1 Rookie
    Owner Silver Subscribed

    Feb 17, 2006
    4,078
    San Jose area
    Full Name:
    Brian Harper
    #12 Brian Harper, Jan 15, 2011
    I only used one once so far a long time ago on my clapped out Honda. The guy at the counter in the bearing shop knew exactly what I needed. It was thin as I recall, maybe .5mm?
     
  13. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    #13 Mark 328, Jan 17, 2011
    A spacer cut on a lathe would be best (with plenty of clearance to the shaft), but years ago on my BB Chevy I used about an .030" piece of plastic from a coffee can lid. It worked for many years, but I no longer have the car.
    The new seal location needs to be just past the groove.

    M
     

Share This Page