Clutch stuck????
Thread Starter
Instructor
Joined: Dec 2003
Posts: 167
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From: Blythewood S.C.
St. Jude Donor '14
Clutch stuck????
Hi guys. Just tried to move my '78L82,4speed. Started fine and depressed the clutch to put it in gear and it was of i had not depressed the clutch at all. Lots of grinding and not even attempting to go in gear. Shut the engine off. So, trying to figure it out, I put it in gear (first or reverse), and hit he starter ,the car lurched forward or reverse. Was trying to maybe "unstick" the clutch. Never have I seen a straight drive do this unless the clutch arm has fallen loose etc. BTW, the clutch pedal feels normal so I guess the spring is ok. Drove it a couple of weeks ago and it did fine. Anyone heard of a stuck clutch? Have not even crawled under it yet to look. Thoughts???? Thanks
Last edited by MGB; Aug 30, 2020 at 07:14 PM.
Le Mans Master
Joined: Jun 2019
Posts: 7,658
Likes: 2,470
From: Indiana
Are you on a slope?
many threads i seen..try rocking the car?
one of many threads search stuck in gear or neutral etc
https://www.corvetteforum.com/forums...k-in-gear.html
many threads i seen..try rocking the car?
one of many threads search stuck in gear or neutral etc
https://www.corvetteforum.com/forums...k-in-gear.html
Racer
Joined: Aug 2005
Posts: 355
Likes: 18
From: Corona Ca
Hello,
I went thru a similar issue with my 70 Elco earlier this year. Driving home, depressed the clutch pedal, shifted, tried to depress for next gear, it was as solid as if clutch assy was made from plate steel. Had to rev match and shift to get home. No noises or warning, no change in engine sound or vibration.
Final analysis upon disassembly was that one of the six cushioning springs had broken out of the clutch disc and wedged between the disc and the fingers of the pressure plate. Took up all of the room for clutch travel and made it solid. No other damage, new clutch set and was back on the road.
Good luck with the repair, I hope yours is as simple as mine was.
Tom
I went thru a similar issue with my 70 Elco earlier this year. Driving home, depressed the clutch pedal, shifted, tried to depress for next gear, it was as solid as if clutch assy was made from plate steel. Had to rev match and shift to get home. No noises or warning, no change in engine sound or vibration.
Final analysis upon disassembly was that one of the six cushioning springs had broken out of the clutch disc and wedged between the disc and the fingers of the pressure plate. Took up all of the room for clutch travel and made it solid. No other damage, new clutch set and was back on the road.
Good luck with the repair, I hope yours is as simple as mine was.
Tom
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
I've had my C3 for over 30 years, back when I lived in Wisconsin, it would sit for 6 months at a time. (Winter). Never had the clutch stick.
I'm thinking you need to take it apart.
I'm thinking you need to take it apart.
Le Mans Master
Joined: Jan 2006
Posts: 6,506
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From: Butler Pa
Had this happens about 30 years ago. Drove through high water from a storm. Got home and pulled up to a curb and parked it. Next day I go to leave, push the clutch in and turn the key. It was in gear and lurched forward, hit the curb and broke loose. The disc had rusted to the flywheel. It was fine after that.
Thread Starter
Instructor
Joined: Dec 2003
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From: Blythewood S.C.
St. Jude Donor '14
Thanks guys for the replies. I'm still searching. I have even put it in gear without the engine running and hit the starter with the clutch pressed. The car lurches. Have done this in both reverse and first gear probably 10 times of so. Seems if the disc and flywheel were stuck together, that would free them looking more and more like 4vettes is on the right trac k. Keep the ideas coming
Thread Starter
Instructor
Joined: Dec 2003
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From: Blythewood S.C.
St. Jude Donor '14
Another thought. Could the transmission be stuck in two gears??? I have no problem with it in neutral. The engine runs in neutral with the clutch in or out and I can press the clutch and gently try to put in gear and immediately start to hear grinding. Also, looked into the clutch fork slot while i get someone to press the clutch and i do see the release bearing definitely moving back and forth, thus the pressure plate is being depressed. Boy, I hate to have to tear this thing down but ya'll can probably tell. lol
Last edited by MGB; Aug 31, 2020 at 03:39 PM.
Melting Slicks
Joined: Feb 2017
Posts: 3,232
Likes: 1,232
From: PHX AZ
MGB. 1969 L-46. Car sat for months in VT. in the cold and condensation cycles. It's Spring! Time to wake it up!
Clutch disk was rusty-welded to the flywheel.
1. Start car...assuming REAR OF CAR is facing out the garage door!!!
2. Remove all impediments.
3. JAM car in gear in reverse....most mechanical advantage.
4. POP! the clutch is free.
5. Operate normally to re-burnish the flywheel.
It's a little scary for a second!
Option B Start car in reverse.....
Good luck...assuming that it's a frozen disc.
Unkahal
Clutch disk was rusty-welded to the flywheel.
1. Start car...assuming REAR OF CAR is facing out the garage door!!!
2. Remove all impediments.
3. JAM car in gear in reverse....most mechanical advantage.
4. POP! the clutch is free.
5. Operate normally to re-burnish the flywheel.
It's a little scary for a second!
Option B Start car in reverse.....
Good luck...assuming that it's a frozen disc.
Unkahal
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Racer
Joined: Jul 2015
Posts: 396
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From: Lehigh Valley Pennsylvania
Another thought. Could the transmission be stuck in two gears??? I have no problem with it in neutral. The engine runs in neutral with the clutch in or out and I can press the clutch and gently try to put in gear and immediately start to hear grinding. Also, looked into the clutch fork slot while i get someone to press the clutch and i do see the release bearing definitely moving back and forth, thus the pressure plate is being depressed. Boy, I hate to have to tear this thing down but ya'll can probably tell. lol
Race Director
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I've had motorcycles with stuck clutches. Fired them up in gear and took off down the road with the clutch lever pulled back to the bsrs. One I drove this way for about a mile before it popped loose.
but you'll need an open road to try this!
but you'll need an open road to try this!
Thread Starter
Instructor
Joined: Dec 2003
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From: Blythewood S.C.
St. Jude Donor '14
Still searching!! Does anyone out there know how much "travel" the clutch release bearing travels when the clutch is depressed? Mine travels at least 1/2 to 3/4 of an inch. I can actually see several springs of the pressure plate moving when the clutch is pressed. I have also adjusted the clutch rod length that comes through the firewall. Thanks
Race Director
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I just put a clutch in mine about a year ago. Car on 4 jackstands, 60 year old man pulling the transmission out by hand. And hiking it back in with brute force. No trans jack or anything like that. New clutch works perfect. But I never thought to measure the distance the throwout bearing moves. Non the less, one would think 1/2 ta 3/4's would be plenty.
Racer
Joined: Jul 2015
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From: Lehigh Valley Pennsylvania
It is a LARs post I remembered from a while ago. Does this help? What have you tried so far? https://www.corvetteforum.com/forums...and-specs.html
Thread Starter
Instructor
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From: Blythewood S.C.
St. Jude Donor '14
Thanks 2mnyvets for the LARS article info. . Very informative. He knows his stuff. All I have done so far is change the travel adjustment length of the clutch rod a little at a time. No change. I will change the length all the way to the end of the rod today and see. Keep in mind that this occurred all of a sudden. All was good the last time it was driven and did not notice or "feel" anything when I parked it. I also observed the "going through the gears" when engine not running with clutch in or out. Gears changed smooth. Also observed clutch operation again and can actually see several of the pressure plate springs being compressed by the throw out bearing. Thanks
Advanced
Joined: Aug 2013
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From: Canton Ga
I had the same thing happen to my 69. I keep it parked in the garage in neutral most of the time and occasionally I go out fire it up and I have the same result. I usually turn it off, push it backwards (not easy) out some and it unlocks and all is fine. Happens about once every 3 or 4 months...It drives and runs just fine.......
Thread Starter
Instructor
Joined: Dec 2003
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From: Blythewood S.C.
St. Jude Donor '14
Hey guys. Well, I think i got it. Put a stick to keep the clutch pressed for a week or so. Started the car and let it idle for a couple of hours to get it at operating temperature. Surprised the hell out of me when I checked it out and the clutch worked as it should. yipeeeeeeeeeeee. Guess it was the clutch sticking to the flywheel after all.
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Glad to hear a happy ending!
Thread Starter
Instructor
Joined: Dec 2003
Posts: 167
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From: Blythewood S.C.
St. Jude Donor '14
OR.... Another thought. SOMETHING was stuck. Was it the actual clutch disc stuck to the flywheel or could it have been the center spline of the disc stuck/rusted to the transmission shaft. Will never know for sure. What do you guys think?
Le Mans Master
Joined: Jun 2006
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From: Tampa Florida
I just put a clutch in mine about a year ago. Car on 4 jackstands, 60 year old man pulling the transmission out by hand. And hiking it back in with brute force. No trans jack or anything like that. New clutch works perfect. But I never thought to measure the distance the throwout bearing moves. Non the less, one would think 1/2 ta 3/4's would be plenty.
Now at 70, installing a starter is about all the weight I can handle.
