348 shaft O-ring (triple seal) question | FerrariChat

348 shaft O-ring (triple seal) question

Discussion in 'Technical Q&A' started by ShanB, Jan 31, 2004.

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

  1. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    I am attempting the dreaded output shaft triple seal installation with some difficulty. I know that Ferrari makes a special tool for this. What exactly is this special tool, what does it look like, and is there a suitable alternative?

    For example, I know Billybob mentioned using a copper pipe, but exactly what do you do with it to get the seals on the shaft?

    Thanks - I will post pics of this also.

    Shan
     
  2. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    It wouldn't happen to be this tool, would it?
     
  3. ferrarifixer

    ferrarifixer F1 Veteran
    BANNED

    Jul 22, 2003
    8,520
    Melbourne
    Full Name:
    Phil Hughes
    Dunk the seals in boiling water until the last possible moment. Then, once installed, let them cool for a few hours to shrink back to size.

    I use shim stock sheets wrapped around the shaft, to slide the seals to their slot without dropping in the wrong one.
     
  4. fatbillybob

    fatbillybob Two Time F1 World Champ
    Consultant Owner

    Aug 10, 2002
    26,367
    socal
    Not me. No on the pipe. I just use fingernails and kinda of force them over the splines. I don't seem to have problems with them dropping in the wrong groove. They are pretty streatched out like mamma givin birth. But with time per Ferrari fixer everything shrinks back well enough to slide the input shaft back home. I always say I'll make a tool but I'm too lazy.
     
  5. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Phil, Billybob - thanks.
    Well I must have stretched mine a little too far - they didn't shrink back AT ALL once on the shaft, so time to try again with new shims. Good thing is they're relatively inexpensive.
     
  6. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Sorry - I meant "seals" not "shims"...
     
  7. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Okay guys, I re-installed the seals by dunking in boiling water. It was actually quite easy to slide them on with finger pressure but boy do they stretch. I'll have to take your word for it that they shrink back:
     
  8. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    closeup showing the gap between the o-ring and the seat:
     
  9. ferrarifixer

    ferrarifixer F1 Veteran
    BANNED

    Jul 22, 2003
    8,520
    Melbourne
    Full Name:
    Phil Hughes
    hmmmm, it does look like there is still a big gap.

    The trick is to only heat and stretch them the absolute minimum necessary. That's why I use the shim material over the grooves/notches......it means less struggling/manipulation/stretching.

    Anyway, wait a few hours, try cooling them with a cold aerosol spray like brake cleaner or a proper temperature reduction spray (wurth).

    Perhaps try to reduce them by putting hose clamps around them for the cooling period? Just a thought.
     
  10. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Thanks. These pics were taken 5 min after putting them on. I'll go check in a few hours or in the morning and see. FWIW, I didn't stretch them any more than what was absolutely required to get them over the shaft so we'll see. Appreciate the advice.
     
  11. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Just to follow up, they did shrink back a little. Then I held them onto the shaft and gently tapped the shaft back in and they molded into the shaft notches again just fine. Problem solved.

    By the way, does anybody know what these o-rings are made of? I'm thinking Viton but not sure.
     
  12. ShanB

    ShanB Formula Junior

    Jul 9, 2003
    547
    Tejas/Europe/Desert
    Full Name:
    shanb
    Okay, am putting the bellhousing back on, and cannot get it to seat all the way. There is still a 1/2" gap between the bellhousing and transaxle. Everything looks like it lines up okay, I slid the assembly over the input shaft and past the splines - then it just stops. So... anybody have any hints?
     
  13. Dr_ferrari

    Dr_ferrari Formula 3
    Consultant Professional Ferrari Technician

    Nov 2, 2003
    1,067
    Pocono Sportscar
    Full Name:
    Jim McGee
    Put the gearbox in gear and rotate one of the wheels with a rocking motion while lightly pressing it on. That will help engage the shaft if it is not aligned with the splines.

    best regards and good luck, Jim
     

Share This Page