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  #1  
Old 08-19-2003, 05:00 PM
pravnik pravnik is offline
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Clutch problem on a '95 Corvette

I have a '95 Corvette that the clutch seems to be giving out on. There's too much play in the clutch pedal and the gears are increasingly hard to shift into; also, you can't shift into first unless the car is completely stopped or the gears will grind, even with the cluch pedal all the way to the floor. Anybody know enough about the inner workings of this clutch to hazard a guess as to the problem? Gary T, maybe?
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  #2  
Old 08-19-2003, 05:18 PM
Berkut Berkut is offline
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Check the fluid level in the clutch master cylinder, first thing.
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Old 08-19-2003, 05:37 PM
Tuckerfan Tuckerfan is offline
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Certain years GM vehicles have problems with the throwout bearings in the transmission. Apparently, GM doesn't like to talk about this, but the only cure (other than periodically having your tranny torn apart and a new throwout bearing installed) is to have a zerk fitting installed in the case so that you (or whomever does the maintence on your car) can grease it routinely. My source for this is the G. Gordon Liddy show. Liddy was bitching because he kept having to have the throwout bearing replaced on his 'Vette. A caller explained the fix for it, so this might not be entirely accurate, but I've never heard Liddy bitch about his car since, so take it FWIW.
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Old 08-19-2003, 06:05 PM
bernse bernse is offline
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While I am not going to shoot down Tuckerfan's advice, I will advise you to be careful if you go that route. It is very easy to overgrease a bearing with a grease gun and that is actually one of the fastest ways to kill one.

That being said, I don't think that is the problem with yours. If the throwout bearing was failing, you'd hear it.

I'll also second you check the fluid level in your clutch cylinder stat.
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  #5  
Old 08-19-2003, 06:55 PM
Gary T Gary T is online now
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My manual shows the car to have a hydraulic clutch operating system (my term for the parts that transmit motion from your foot on the pedal to the clutch mechanism). The symptoms described are exactly what I would expect if there were a hydraulic problem, usually a leaking clutch master cylinder or clutch slave cylinder. So I agree with Berkut and bernse, that's the first thing to check. Statistically, this is far and away the most likely cause of the problem.

If the level is low in the clutch fluid reservoir, that would indicate an external leak. You can top it up (use brake fluid) and possibly improve function for a time, but the cure will be to replace the leaking cylinder(s). Even if only one cylinder is leaking, it's not a bad idea to replace them both--when one goes, the other is often not far behind.

If the reservoir is full, no external leak, it could still have a faulty cylinder that leaks internally. A competent repair shop can test for this.

If it is determined that the hydraulic operating system is working properly, then the problem has to be in the clutch mechanism, what is usually meant when talking about "replacing the clutch."

The hard shifting/grinding of gears is pretty rough on the transmission, so it's wise to get this fixed ASAP.
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  #6  
Old 08-20-2003, 09:50 AM
pravnik pravnik is offline
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Thanks guys. I was told that I had a cable clutch and there was no fluid to replace, and didn't think otherwise until y'all set me straight. Sure enough, the reservoir was bone dry, and putting fluid in cleared the problem up 100%.

So, is replacing the clutch cylinders something a novice can do successfully, or is it something best left to the pros?
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  #7  
Old 08-20-2003, 10:33 AM
Gary T Gary T is online now
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Detaching and reattaching the cylinders is fairly straightforward, however, there are two concerns.

Access. The slave cylinder is underneath the car, which would have to be jacked up with enough room to work. The master cylinder is obscured by the battery and an insulation panel. My estimator book indicates it has a fairly high pain-in-the-butt quotient.

Bleeding. After replacing the cylinder(s), it will be necessary to bleed the air out the system. This is done at the slave cylinder, underneath. Sometimes it goes smoothly, and sometimes it's a frustrating pain. It's usually difficult or impossible without special tools or an assistant.
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  #8  
Old 08-20-2003, 04:20 PM
bernse bernse is offline
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As well, I wouldn't replace it right off the bat. Carefully look around the cylinder and hose for leaks/damp spots. You might not even need to replace the cylinder, it could be a hose or something else (although, I'll admit, there isn't a whole lot else in a clutch that could leak).

I'll also through in that it might be a good time to change your tranny oil, especially if you've been grinding the gears a lot lately.
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  #9  
Old 08-20-2003, 06:05 PM
pravnik pravnik is offline
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Excellent. Thanks, guys.
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