Can't go anywhere
 

Hey all. I have a 1976 corvette with a 4 speed. Just recently got a hold of it. I am under the impression that the clutch will not disengage. I can shift into all gears with the engine started and without pressing the clutch pedal. Where should I start in trying to diagnose or fix this problem? Thanks

Can you push the car with it in gear? Do the gears grind while your shifting them with the engine running? Funny noises while it's running? look for a broken input shaft or a missing driveshaft. Have a look underneath....

You can shift the car into all gears without stepping on the clutch while the engine is running? Does the car go anywhere or is it sitting still? If it's not going anywhere at all, something is broken. And are you sure it's the clutch won't engage, not disengage?

My sister drove our 68 Falcoln home stuck in 3rd. Slipped clutch till it got so hot it softened and collapsed the springs in the pressure plate. Could also be clutch disk so shot the slip is total.

Generally if clutch won't disengage, you crank motor in first and drive away, shifting without clutch til you hafta stop. Shut off. Put in first. Start motor in first when light turns green.

alot of things have been llisted as possible problems and you have to crawl underneath to check them.

1. disconnected shifter (not likely)
2. disconnected diveshaft (it would still be tough to shift and possibly grind)
3. blown clutch (most likely)
4. broken input shaft ( might hear grinding but might have stopped since PO had it)
5. too much cough medicine.....just saying to round out the list
6. blown rear differential ( again spinning everything and shifting, the tranny would still grind and make noise

sounds like you need a new clutch. Either way, you're going to have to pull the tranny and have a look. Theres no way you can shift the trans with the car running and have it go into all gears and there not be something broken. Hopefullly its the clutch, its easy to replace, you can match it to your horsepower output and you will know its history. If its the input shaft then you have to tear the tranny apart to fix it. Its pretty straight forward but it'll cost you you more. IF there is metal floating in side the tranny you'll want to replace everything in there.

I pull the engine to get the tranny out easily because the tranny cross member is welded in, maybe the PO changed that if your lucky. Some people say they drop theirs with the engine in but its a hassle, especially if your on the groud, on your back and dont have any room

I blew a clutch in a Jeep CJ7 trying to pull my buddies F250 dump up a hill and it just shredded. Same symptoms as you

I can push it while it is in gear. The gears dont grind when shifting while it is running. No funny noises that I can hear. All shafts present.

shifter is connected. driveshaft is comnnected. I am thinking maybe blown clutch. Looks like I am gonna have to dig deep.

Well then, I'd get underneath and have a look at the clutch disc and see whats left of it....a new one is about 3/8" thick so you can use that to judge what you have left.
Then you need to drain the transmission oil and the rear end oil (suck the rear end oil out) and see if any parts come out with the oil....

Any recommendations for a good replacement clutch?

Most likely a clutch issue, but the possibility exists it is the rear end that is smoked. Put the car in the air and see if you can turn the rear wheels without the driveshaft turning. If the rear appears intact, the problem is in the clutch and/or transmission. If that's the case, your next step is to remove the transmission and clutch for inspection. It might be easier to convert the transmission crossmember to be removable than to remove the engine.

Are there any post on how to go about making the conversion?

Hays has always made a good high performance clutch. It's what I use in my '65.
https://cimg0.ibsrv.net/gimg/www.cor...786186983c.jpg

I use McLeod but they rate their clutches by HP so you need to research that part.

For the removable crossmember mod,I think there was a couple of posts on how to do it. I havent done it myself, yet. I have the parts though

https://americanpowertrain.com/i-238...corvettes.html

https://www.corvetteforum.com/forums...ossmember.html

This works. Years ago, I hauled 40,000 pounds of swinging meat from the packing house in Garden City Ks, to Kansas City. When I backed the trailer into the dock in Garden City, something went "POP" and no more clutch. Found out the center hub had broken out of both discs.

Perfection Clutch aka Brute Power
http://www.perfectionclutch.com/products.htm
They were primary sponsor on asphalt circletracker we used to own. Perfection manufactures near me which is also close to Darlington.
Perfection were good to us ... yes, we ran their flywheel, disk and pressure plate ... so I must recommend Perfection.

That would work but the car doesn't move at all. I have to depress the clutch to start the car, but when i left it out....nothing.

There are several ways to go about it. Aftermarket crossmembers are available. I think Bowtie Overdrives is one supplier, and there are probably others. My car started life as an automatic so it has the removable crossmember. I'm sure it is possible to retrofit that factory piece. If it were me, I would probably cut the factory crossmember and fabricate a couple of plates bolted together and weld them in. I know I've seen pictures of that being done on this forum. If you search long enough maybe you'll find them. If you get lucky maybe one of the guys who has done it will respond to this thread.

Take some pics of your z-bar, clutch lever, and the assembly near the bellhousing. Perhaps something may be noticed by multiple eyes on it?

I'll take some tomorrow.