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348 clutch gearbox problem

Discussion in 'Technical Q&A' started by spider348, Nov 3, 2003.

  1. spider348

    spider348 Formula 3
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    Nov 3, 2003
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    John
    Appear to have developed a perplexing clutch/ gearbox problem. Problem has been getting progressively worse over the past 6 months. Ferrari is a 1994 348 spider with 48k miles.
    Symptoms are difficult to engage 1st, sometimes any gear from neutral. Difficulty seems slightly worse when warm. Generally engages with no problem cold. Neutral at a stoplight, will not shift into 1st. Often will shift into 1st with no effort if reverse or 2nd engaged before 1st. Recently all gears difficult to engage when stopped. After start, all gears change etc with no difficulty.
    When difficult to engage, there is a slight sound, lever will not enter gate. No grind or chatter felt through the lever. May be slight car motion as found in a dragging clutch, not sure.
    Clutch engages over halfway from floor. Action feels normal. No improvement if I pump the pedal. No leaks at the clutch area that I can detect. Recently bled with a MityVac, not sure if correctly done. Adjusted linkage, lever centered in the gate.
    Comments welcome, thanks for the help.
     
  2. matteo

    matteo F1 World Champ

    Aug 1, 2002
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    Heir Butt
    Could be two things.

    Broken motor mount or shifter linkage out of alignment
     
  3. Caruso360

    Caruso360 Karting

    May 1, 2003
    203
    The 348's have two sealed shift cables which run from the gear shift lever
    to the transmission. My 348 had a seized cable which caused difficulty in shifting.
    The cables run about $600 bucks a piece. Good Luck
     
  4. spider348

    spider348 Formula 3
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    Nov 3, 2003
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    Matt, Caruso360, thank you.
    I adjusted the shift linkage several months ago because the lever was slightly off center. Lever is currently centered in the gate. This is not to say the linkage is indexed correctly to the transmission. Is there a method to confirm alignment short of dropping the pan and viewing the shift forks? Align the yoke on the transmission shift rod and align the lever from that datum, regardless of lever position in the gate?
    Broken motor mount. I would suspect the difficulty would increase under load due to torsional stress. Shifts fine under load. Still, another possible cause, I will check.
    Cables. Cable action appears to be free but I will disconnect from the yoke and confirm condition.
    Feels like clutch drag but I am mystified by the lack of grinding or chatter when I try to engage. The lever literally stops at the gate opening as if it was blocked.
     
  5. matteo

    matteo F1 World Champ

    Aug 1, 2002
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    Heir Butt
    Did this occur all of the sudden or has it been overtime?
     
  6. Caruso360

    Caruso360 Karting

    May 1, 2003
    203
    When all else fails give Dave Helm's a jingle at 303-449-9112. He's by far the best authority on F cars.
     
  7. Caruso360

    Caruso360 Karting

    May 1, 2003
    203
    Give Dave Helm's a jingle, 303-443-5231. By far the best authority on F cars.
     
  8. tbakowsky

    tbakowsky F1 World Champ
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    Sep 18, 2002
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  9. Allen S.

    Allen S. Formula Junior
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    Mar 16, 2001
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    Allen / AKA tCoupe
    I had the same type of symptoms with my "t" a couple years ago. The problem was that the main drive seal between the clutch and the gear box had cracked and leaked. The gear fluid was getting onto the clutch disks and making it hard to engage/disengage the clutch. I had the same type issues with selecting gears like you. Clutch pedal always felt ok.

    Look into the inspection plate on the clutch housing to see if you have fluid residue. I never had fluid on the garage floor, just enough inside the housing to cause the problem. Hope this helps.
     
  10. Ferrari_tech

    Ferrari_tech Formula 3

    Jul 28, 2003
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    Malcolm W
    A simple way to check the gear adjustment is with the gear lever in neutral, push it forward into 3rd gear and see how far it travels up the gate, then pull it back to 4th and compare the travel - if there is a difference you need to adjust the engagement cable.

    Having done that remove the gear lever gate and select third, move the lever to 1st then to 5th and compare the distances travelled - as above if there is a difference then adjust the selection cable.

    If the cables need adjusting you may need to have several attempts to get it right - good luck.

    MW
     
  11. rexrcr

    rexrcr Formula 3

    Nov 27, 2002
    1,572
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    Rob Schermerhorn
    To me, this sounds like driving a high milage manual transmission. Syncros are wearing a bit, but not enough to justify rebuild. It sounds like when all the gearbox components are motionless, it's nigh impossible to engage. Try (if you haven't already figured this out) "double clutching" while motionless, this spins the input shaft and may allow enough motion in the gearbox to help the syncros engage the gear.

    I do this all the time out of habit with any car that's difficult to get into first. I also do the 'engage second to help it into first' deal too.

    Certainly check alignment as suggested. That, new gear oil, and a good bleed (which you've done) are really the only inexpensive maintenance you can do before opening up the 'box.

    HTH,

    Rob Schermerhorn
     

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