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308 Camshaft Seals Falling Out

Discussion in '308/328' started by CR500, Feb 8, 2020.

  1. CR500

    CR500 Rookie

    Feb 1, 2020
    2
    Full Name:
    Robert Gallant
    Hi Everyone,

    Have a question about a friends car. Its a 1975 Dino 308Gt 4+2.

    The camshaft seals on the front of the engine (passengers side) started coming out. We pulled the engine for some maintenance including cam belts, seals, tensioners, water pump, and a good cleaning. It fired right up but the seals popped out after about five min of run time. Its primarily on bank 1 (towards rear of the car) but I believe he has had them come out from the other bank as well.

    I'm thinking that I'll check the bore dimensions (with valve cover gasket in place) to see if its out of round or tapered, and how it compares to the seal OD.

    Any ideas?

    Thanks!

    Rob
     
  2. absostone

    absostone F1 Rookie
    Silver Subscribed

    Jul 28, 2008
    4,739
    Fchat
    From what has been said here it is best to hold the seals in place while tightening down the cam covers. Also centerpunching all around the bore area prior to installing the seals will give grip to the seal and prevent movement while tightening the cam covers
     
  3. Nino1964

    Nino1964 Karting

    Aug 14, 2015
    166
    North Georgia
    I use a slight bit of Hondabond around the perimeter of the seals as part of my installation process.
     
  4. Rifledriver

    Rifledriver Two Time F1 World Champ

    Apr 29, 2004
    26,849
    Austin TX
    Full Name:
    Brian Crall
    Check for crankcase pressure and that the crank breather system is working as it should. Some of the 2 cam cars have had that problem. I dont think sealant is the best approach. I have seen small dimples or punch marks around the hole work well.
     
    smg2 likes this.
  5. tbakowsky

    tbakowsky F1 World Champ
    Professional Ferrari Technician Consultant

    Sep 18, 2002
    14,829
    The Cold North
    Full Name:
    Tom
    What gaskets are you using for the cam covers? If they are too thick, the cover will not clamp the seal enough to hold it on place. Make sure the gaskets are not a cheap aftermarket brand.
     
  6. absostone

    absostone F1 Rookie
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    Jul 28, 2008
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    interesting point, is that really possible? has that ever happened?
     
  7. tbakowsky

    tbakowsky F1 World Champ
    Professional Ferrari Technician Consultant

    Sep 18, 2002
    14,829
    The Cold North
    Full Name:
    Tom
    Yes..it is possible and it has happend to me with customer supplied parts.
     
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  8. absostone

    absostone F1 Rookie
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    Jul 28, 2008
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    What is it about the parts, out of spec?
     
  9. CR500

    CR500 Rookie

    Feb 1, 2020
    2
    Full Name:
    Robert Gallant
    I'll ask him about the gaskets. Any idea which brands to use or avoid, or what the correct thickness is?

    I think I checked for crankcase pressure but will put that on the list!

    Hadn't thought of punch dimpling. May give that a shot!

    He didn't use Hondabond, but did try generic orange silicone gasket goop. I was afraid it would act as a lubricant. It didn't work. I was thinking of trying the old Indian Head gasket shellac. In the 70's, I used it on cork valve cover gaskets (both sides by mistake) and almost couldn't get them back off. Took a pry bar and a lot of sweat.

    Another thought was cutting a thin strip from double sided sand paper to squeeze between the seal and aluminum. But it might be too thick.

    Thanks for the ideas!
     
  10. Steve Magnusson

    Steve Magnusson F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    18,733
    Texas
    Full Name:
    Steve Magnusson
    +1 -- my ex-308 came to me with 6~8 equi-spaced centerpunch divots in the area around the seal OD to give something for the flexible material on the OD of the seal to deform into to help retain it.
     
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