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shifting problem

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Old May 11, 2010 | 09:31 AM
  #1  
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From: San Jose
shifting problem

Just got the car all back together after motor rebuild. Trying to get on the dyno but have a shifting problem. Car is an FD with stock tranny, Exedy twin disc clutch.

Symptom, car is very hard to get into any gear when engine is running. No problem shifting with engine off. Noticed with the car on jackstands that even with clutch pedal fully depressed, if I put pressure on going into any gear then the rear wheels will start spinning.

So, my guess is the clutch is not fully disengaging and/or the pilot bearing got farked putting the tranny back in. Tried a clutch bleed late last night with the wife, didn't do a very good job and it actually seemed to be worse. Thinking I need to do another bleed on the clutch before pulling the tranny and looking for something else wrong or replacing the pilot bearing.

Any thoughts? Sound like a clutch issue to you or pilot bearing or something else.

Btw, can't really hear any unusual noise if it were the pilot bearing, but it is a pretty noisy car to begin with.

-Andy
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Old May 11, 2010 | 09:59 AM
  #2  
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Is there any adjustment available in the clutch pedal rod? I just installed a new clutch of a slightly different style in my fb, and had to lengthen the rod a bit to get full disengagement. Not sure how that works on the fd though.

Good luck...



.
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Old May 11, 2010 | 10:03 AM
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Andy, I'm assuming the clutch has been in the car prior to the engine build and working without issue? You disconnected the slave cylinder from the transmission when you removed the engine and left everything else attached? Def sounds like a clutch/clutch component issue. No grinding when you are trying to get it into gear, just difficulty getting it into gear? I'd try bleeding it again to start with. If it did get air into the system, it can be very difficult to get out sometimes.
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Old May 11, 2010 | 10:09 AM
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From: San Jose
Yes, same stuff as was in the car. I was pretty careful reinstalling so I'm hoping the bleeding is the problem. Once in gear the car drives just fine, no unusual noises, clutch feel normal.

Will try to bleed it again today and cross fingers as I really really don't want to pull the tranny out.

-Andy
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Old May 11, 2010 | 10:17 AM
  #5  
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If the clutch pedal feels normal and the clutch is the same I'd say bad clutch fork. If the clutch is soft it could be air in the system but if you've already bled that's doubtful.

If the clutch is new I'd try adj the clutch rod as suggested. The fatter twin plate clutch plates will move the throw out bearing position back and the clutch fork position forward so the slave has to extend further to pull the clutch back.

Finally it may be as simple as the not getting the snap ring on the clutch snapped in place.
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Old May 11, 2010 | 01:28 PM
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From: San Jose
Rebled the clutch again and made sure to take out any free play in the clutch pedal. I had noticed there was some unused travel in the pedal so took almost all that out. Now it disengages the clutch more and seems to be ok. Why it wasn't an issue before not sure, must have been borderline.

Never been happier to hear the twin disc rattle.

Thanks for replies.

-Andy
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Old May 11, 2010 | 04:29 PM
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Yep. Sounds like a clutch fork but I guess its not.

I have a newer, reinforced, 20k mile one that I'll let go for cheap if you need it and want to save a few bucks.
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