Topic: Clutch Travel
in Forum: C3 Driveline Components
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I have installed a 383 and added a Lakewood bellhousing in my 1975. I have the clutch rod nuts extended to the max and I still need to almost push the clutch pedal through the floor to shift gears. Any ideas on how to resolve this?
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should be about 1 inch freeplay at the pedel, was the clutch fork ball adjusted in the bell housing the proper distance from the inside of the bell housing trans flange to the ball, did you check the fork to see if it was bent or broken, did the fork happen to slip off the ball when you installed the tranny, are you sure the shift linkage is adjusted properly ?anips 2010-06-05 18:42:53
All good suggestions. Bottom line, gotta find out why full pedal travel is required to get the pressure plate off the disk. Likely in the linkage or fork geometry. I have seen minor deviations in the bellhousing mating flange cause problems.
Scott
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
[QUOTE=anips]...was the clutch fork ball adjusted in the bell housing the proper distance from the inside of the bell housing trans flange to the ball...[/QUOTE]
That would be my guess, also. The ball should be threaded into the bellhousing, and is normally adjustable for such scenarios as this. There are also different length balls for different applications.
If you used your original fork, then that should be ok. The only difference is the bellhousing, which is not likely to be made exactly the same as the GM part, so the geometry is prolly gonna be off somewhere.
Did you change the clutch assy also?
Joel Adams
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OK, I have done some research on this and it looks like there are two diffrenet release bearings with diffrent dimensions. I guess AI have to take the trans out and get in there agian and check the release bearing dimensions and also see how the pivot adjustment can help out my predicement.
While this link talks about Jeep clutches, the technical information pertains to Corvette clutches.
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20219
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
So you did change the clutch assy too? There are two different bearings...a short one, and a longer one. You may have the shorty, and need the longie. There's not a lot of difference in the length if you put them side-side, but it makes a huge difference in pedal travel. A 1/4" difference in the TOB can make a 1" difference at the pedal, due to the geometry of the fork, and the linkage. 
Joel Adams
C3VR Lifetime Member #56
My Link
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
great info, usually when I replace the clutch I buy a clutch kit for the application, it comes with everything, if you got to slide the tranny back and start over you might want to check the clutch linkage like the z-bar, rods, pedal, fork, over the years the holes get bigger causing slop, I replace the pieces or weld up the holes and redrill em, I replaced the z-bar to clutch fork rod with Heim ends, makes for a smoother operation.
Joel is 100% correct. A minor deviation at any mating interface is greatly amplified at the clutch pedal. The geometry is very sensitive to any deviation from the factory spec.
Scott
I have also read that there are two different release bearings. I used the one that came with the clutch kit. I should have checked the movement and clearance.
The clutch fork has a large lever and a small diffrence in bearing thickness will make a hugh difference in clutch travel.
Oh well, guess tranny needs to come out to verify what's wrong.
Do you think I can pull 4 speed manual tanny and leave exhaust system connected?
Lifetime MemberModerator
Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Depends on the exhaust system(stock or not), and how much you like having skin on yer hands...
Then again, your's is a '75, so with the cat converter, and the "Y" pipe up there...might be best to drop the front down, at least.
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
in Forum: C3 Driveline Components
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