Slipping (new clutch)
#1
Launching!
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Slipping (new clutch)
Hi all,
Fresh rebuild LE2 H/C/I on 1995 Z28
Resurfaced the flywheel, new Spec stage 2 clutch and new clutch fork.
Finally got the car street legal and on the road and it is slipping badly.
Where do I start?
Fresh rebuild LE2 H/C/I on 1995 Z28
Resurfaced the flywheel, new Spec stage 2 clutch and new clutch fork.
Finally got the car street legal and on the road and it is slipping badly.
Where do I start?
Last edited by LarsV8; 08-04-2011 at 10:34 PM.
#2
Launching!
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could be the slave. my car is stock and the slave cant even hold the power, clutch is also stock but only has 20,000 miles on it, the slave has cause it to wear out. im replacing the whole system next week tho
#3
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Doubt its the slave, a bad slave wouldn't cause clutch slipping on an LT1 setup.
Check for any transmission fluid leaking from the input shaft seal. I had a really slow input shaft seal leak that caused me to burn through two brand new Spec clutches in under a couple hundred miles before the leak got fast enough to leave obvious evidence.
If the input shaft seal is shot, fluid just runs straight down the shaft and into the clutch hub, centrifugal force takes it from there.
Couldn't hurt to install a new pilot bushing if you haven't already. If the old one's worn out enough, it will cause some play in the input shaft itself, which doesn't make it any easier for the input shaft seal to contain the fluid.
Check for any transmission fluid leaking from the input shaft seal. I had a really slow input shaft seal leak that caused me to burn through two brand new Spec clutches in under a couple hundred miles before the leak got fast enough to leave obvious evidence.
If the input shaft seal is shot, fluid just runs straight down the shaft and into the clutch hub, centrifugal force takes it from there.
Couldn't hurt to install a new pilot bushing if you haven't already. If the old one's worn out enough, it will cause some play in the input shaft itself, which doesn't make it any easier for the input shaft seal to contain the fluid.
#4
I assume that this slippage is occuring after a recent install. That being said I have a few questions:
1. Did you check the flywheel for flatness and plane before install?
2. Did you check measurements relative to need of the shim?
3. Did you have to pull the transmission on with bolts?
4. Have you noticed any leaks from the bell? Are you seeing the fluid level in the reservoir go down?
5. How many miles are on the clutch?
6. what is your torque output?
Answers to these questions will help me better assess the situation. Thanks and let me know if you have any questions of your own.
1. Did you check the flywheel for flatness and plane before install?
2. Did you check measurements relative to need of the shim?
3. Did you have to pull the transmission on with bolts?
4. Have you noticed any leaks from the bell? Are you seeing the fluid level in the reservoir go down?
5. How many miles are on the clutch?
6. what is your torque output?
Answers to these questions will help me better assess the situation. Thanks and let me know if you have any questions of your own.
#5
Launching!
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I assume that this slippage is occuring after a recent install. That being said I have a few questions:
1. Did you check the flywheel for flatness and plane before install?
2. Did you check measurements relative to need of the shim?
3. Did you have to pull the transmission on with bolts?
4. Have you noticed any leaks from the bell? Are you seeing the fluid level in the reservoir go down?
5. How many miles are on the clutch?
6. what is your torque output?
Answers to these questions will help me better assess the situation. Thanks and let me know if you have any questions of your own.
1. Did you check the flywheel for flatness and plane before install?
2. Did you check measurements relative to need of the shim?
3. Did you have to pull the transmission on with bolts?
4. Have you noticed any leaks from the bell? Are you seeing the fluid level in the reservoir go down?
5. How many miles are on the clutch?
6. what is your torque output?
Answers to these questions will help me better assess the situation. Thanks and let me know if you have any questions of your own.
2.) I thought the LT1 cars did not need shims, we did not use one.
3.) Yes I think we did.
4.) Havent noticed any leaks, will check the resevoir.
5.) Probably less than 50
6.) Using LE2 heads and a 226/230 cam, so I guess maybe 390 at the wheels?
#6
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LT1 cars don't use shims. A handful of LT1 guys make their own shims to space the flywheel out further after its been resurfaced a lot, but this has never been proven to correct or improve clutch operation.
Drop your tranny and get a good look at your friction disk. Check for any tranny fluid, not clutch fluid, on the hub of the friction disk.
When my input shaft seal was leaking, it was fast enough to ruin a clutch disk, but too slow to cause any dripping or anything noticeable on the underside of the car.
Drop your tranny and get a good look at your friction disk. Check for any tranny fluid, not clutch fluid, on the hub of the friction disk.
When my input shaft seal was leaking, it was fast enough to ruin a clutch disk, but too slow to cause any dripping or anything noticeable on the underside of the car.
#7
Sorry, I guess I missed that this was an LT application. The LT should not require a shim. That being said slippage on a Stage 2 will generally point at some form of contaminant being present, as mentioned above by tbag. Unfortunately assessing this will require the parts to be removed.