Installing a 4 speed in a C3
Le Mans Master
Joined: Apr 2005
Posts: 6,360
Likes: 429
From: Seattle Area WA
Did you change the clutch or something? If so, did you use an alignment tool to line up the clutch disk so the trans input shaft will slide into place?
Last edited by Scott Marzahl; Feb 29, 2008 at 11:58 PM.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Have a helper depress the clutch pedal while you rotate the output shaft (trannie in a gear) and push the trannie forward. The input shaft has not lined up with the clutch disc splines. Common problem.
Racer
Joined: Oct 2004
Posts: 281
Likes: 9
From: New England
!st time I replaced my clutch Napa gave me the wrong plate with the incorrect spline . There are two splines , one is a 18 and the other ( I think ) is 24 . I'm not sure how far it stuck out without going in but I can tell you that it took me about an hour of trying before I finally pulled it back out and figured out what was wrong. I was almost ready to back it out of the garage and check on my fire coverage.
I think your going to have to take it back out and do a look see on the front where the Pilot bushing is. Do you have 2 -6" 5/8 bolts with the heads cut off installed on the two top bell housing holes? If not do so, it sure makes it easier to slide the trans in the last 6 inches and pretty much lines it right up too.
Dario
I think your going to have to take it back out and do a look see on the front where the Pilot bushing is. Do you have 2 -6" 5/8 bolts with the heads cut off installed on the two top bell housing holes? If not do so, it sure makes it easier to slide the trans in the last 6 inches and pretty much lines it right up too.
Dario
Melting Slicks
Joined: Jan 2004
Posts: 3,247
Likes: 210
From: Detroit MI
10 and 26
But it sounds like he's into the clutch spines; if an alignment tool was used for the clutch disk-to-pilot bushing, a little wiggling and it should go into place. The pilot bushing is a tight fit on input shaft, and you've got all that weight (the trans) cantilevering off the back-push up on the back of the trans a bit and give it a little wiggle-it should slide right into place.
If an alignment tool wasn't used then all bets are off.
I wouldn't depress the clutch; if the input shaft isn't lined up with the pilot bushing and you push the clutch it'll throw everything off. Then the trans has to come down again, and the disk will need to be lined up again-with an alignment tool.
But it sounds like he's into the clutch spines; if an alignment tool was used for the clutch disk-to-pilot bushing, a little wiggling and it should go into place. The pilot bushing is a tight fit on input shaft, and you've got all that weight (the trans) cantilevering off the back-push up on the back of the trans a bit and give it a little wiggle-it should slide right into place.
If an alignment tool wasn't used then all bets are off.
I wouldn't depress the clutch; if the input shaft isn't lined up with the pilot bushing and you push the clutch it'll throw everything off. Then the trans has to come down again, and the disk will need to be lined up again-with an alignment tool.
Last edited by 69autoXr; Mar 1, 2008 at 07:52 PM.
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Pro
Joined: Nov 2003
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From: Peabody Ma.
Depressing the clutch will not throw any thing off! All it will do is let the disc move a little, Hes already on the disc, if not it would be more like 3" off not a 1/2 off. We have to do this to 4wd trucks when we replace the clutch. The aligment tools are perfect and often let the disc sit a little low!
Melting Slicks
Joined: Dec 2000
Posts: 3,363
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From: Lansdale 19446 PA
2024 C3 of the Year Finalist- Unmodified
St. Jude Donor '10-'11, '15, '19
Not 100% aligned with the pilot bearing. I ddin't have a helper so I used a com-a-long on the fork - tranny slide right in.
Thread Starter
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From: Chesapeake Virginia
Intermediate
Joined: Nov 2007
Posts: 40
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Hi guys. While on the subject of C3s with a 4 spd transmission. Can anyone tell me why my '81 has started grinding the gears when I go to shift in reverse. I have no problems and the forward gears all synchronize smoothly. In order to shift into reverse without the heavy grinding noise, I have to run through several of the forward gears first. What do I need to do? Does this represent a major problem with the transmissions. By the way, the vehicle has 50,000 original miles, I'm the second owner and it has never been raced or wrecked.
Your very informative responses will be greatly appreciated.
Your very informative responses will be greatly appreciated.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
Hi guys. While on the subject of C3s with a 4 spd transmission. Can anyone tell me why my '81 has started grinding the gears when I go to shift in reverse. I have no problems and the forward gears all synchronize smoothly. In order to shift into reverse without the heavy grinding noise, I have to run through several of the forward gears first. What do I need to do? Does this represent a major problem with the transmissions. By the way, the vehicle has 50,000 original miles, I'm the second owner and it has never been raced or wrecked.
Your very informative responses will be greatly appreciated.
Your very informative responses will be greatly appreciated.