 Shift Fork, How much vibration is normal? |
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| Nickm1 |
 May 21 2006, 07:49 AM
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#1
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Member  Group: Members Posts: 76 Joined: 22-April 05 From: Madison Heights, MI Member No.: 3,966  |
when the car is running the fork is like vibrating back and fourth pretty violently. How much movement is normal to see? I think this movement is what is making the nuts on the end of the clutch cable loose.
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| davep |
May 21 2006, 08:03 AM
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#2
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914 Historian Group: Benefactors Posts: 5,143 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada  |
Are you talking about the TO bearing fork?
If so I'd be checking the bearing, the two bushings on either side, the ball cup bushing and the alignment tube. I'd say something is wrong there. |
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| Nickm1 |
May 22 2006, 06:32 AM
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#3
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Member Group: Members Posts: 76 Joined: 22-April 05 From: Madison Heights, MI Member No.: 3,966 |
Yea thats it, I put in a new clutch last summer so it has a new TO bearing. but the bushings and tube, I have no idea what you are talking about. There was just one other spot the TO fork sat on and I greased that up real good.
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| davep |
May 22 2006, 07:55 AM
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#4
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914 Historian Group: Benefactors Posts: 5,143 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
There are two black plastic bushings that sit on either end of the pins of the TO bearing, and bear against the inside of the fork. They position and cushion the TO bearing. 901-116-825-11
At the fulcrum point of the fork there is a ball socket for the fork to pivot on. Inside the fork is a white plastic cup that receives the ball. If the cup is worn out the fork will be loose on the ball. 901-116-741-01 The TO bearing slides on a tube when you depress the clutch pedal. If the tube is worn, then the TO bearing can rattle. Since the TO bearing is always in contact with the pressure plate there is always a source of vibration. The TO bearing is in a very hostile environment, heat & vibration are always present, but the bearing itself is not really lubricated. If you were to lubricate the balls in the bearing it would just attract and keep dirt that would in turn grind down the balls. So the plastic parts are essential to keeping the TO bearing alive. I always replace the plastic parts when I go in there. Attached image(s)  
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| Nickm1 |
May 22 2006, 09:01 AM
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#5
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Member Group: Members Posts: 76 Joined: 22-April 05 From: Madison Heights, MI Member No.: 3,966 |
hmm, I don't have any of that. Everything in there was metal on metal. I have pictures at home I'll have to post them. Maybe something is different since I have a V8.
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| davep |
May 22 2006, 09:28 AM
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#6
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914 Historian Group: Benefactors Posts: 5,143 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
Oh, right, didn't notice, in that case all bets are off.
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| Nickm1 |
May 22 2006, 08:46 PM
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#7
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Member Group: Members Posts: 76 Joined: 22-April 05 From: Madison Heights, MI Member No.: 3,966 |
Here is the only picture I have, It is the old piece I pulled off before putting on the new bearing.
http://pg.photos.yahoo.com/ph/nicksws6/det...dnm=26d4scd.jpg You can see there isn't any bushings where the fork holds onto the bearing. And the opening where the fork goes through, the fork vibrates from side to side in about 1/4 of that space. |
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| Nickm1 |
May 23 2006, 07:26 PM
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#8
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Member Group: Members Posts: 76 Joined: 22-April 05 From: Madison Heights, MI Member No.: 3,966 |
now that i think about it, would it be vibrating if the input shaft was bent. is there another way to know if it is bent
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| davep |
May 23 2006, 09:11 PM
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#9
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914 Historian Group: Benefactors Posts: 5,143 Joined: 13-October 03 From: Burford, ON, N0E 1A0 Member No.: 1,244 Region Association: Canada |
If the input shaft was bent you probably would have a massive tranny oil leak. In the /4 the nose of the input shaft is centered in the bearing inside the flywheel. That does not leave much room if it is not straight and aligned.
The TO fork looks normal, can't tell much about the TO bearing. If it was not a snug fit it would be a problem. That is what the bushings are for with the normal TO bearing. The ball cup is still in there. |
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