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Old 08-17-2012   #21
LGAFF
 
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Default Re: clutch engagement; early

Swapped the slave, no change
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Old 08-18-2012   #22
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Default Re: clutch engagement; early

I hate to say it Lee but it's possible you have a bent clutch fork. Mine would engage right off the floor. And I'm sure you remember it caused me to loose three TB's. Here's the good one next to the bent one I had. Of course that means another transmission pull.

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Old 08-18-2012   #23
XfireZ51
 
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Default Re: clutch engagement; early

Lee,

Before you do the trans pull, make sure you have checked the seal orientation on the slave. They could come that way from the factory.
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Old 08-18-2012   #24
Marc Haibeck
 
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Default Re: clutch engagement; early

Lee,

Has the low pick-up condition been present since you installed the clutch or was it okay and then the low pick-up developed?

I have never seen a low pedal caused by a defective master or slave cylinder. It could be caused by air in the system. If there is air, the free play at the top of the pedal will be excessive. The pedal free play should be less than one inch. The system self bleeds nicely. Since you have been driving the car it should be bled free of trapped air.

I wonder if the clutch disk is too thick? The OE thickness of a new disk is .320”. I have seen disks with too much marcel. That’s the wavy shim under the facing. The OE solid hub disk has very little marcel. I have seen sprung hub disks that are .325” thick. More than that and the pedal disengages the clutch closer to the floor. The pressure plate can be shimmed to compensate for a thicker disk.

If the clutch was okay when new and this has developed, the facing may have failed and is peeling up, making it act thicker than it really is.

I once encountered a car with one inch thick floor mat that caused the problem. Once had a car with two floor mats. The second mat rolled up and caused intermittent no-cranking.
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Old 08-18-2012   #25
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Default Re: clutch engagement; early

Marc is probably right. If this condition developed after a clutch swap. Mine always engaged right off the floor because my clutch fork was bent long before I bought the car. What could bend a clutch fork like mine was is beyond me. Engagement is totally normal after replacing the bent fork. Just out of curiosity Lee did you reverse bleed the slave?
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Old 08-18-2012   #26
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Default Re: clutch engagement; early

The clutch has good pressure at the pedal and engages well, I have to go with marc and say its something to do with the pressure plate or the clutch disc itself.

The problem off the floor is new since the install; I think the issue might be the slow leak from the rear seal(or it could be off the front trans seal). I am thinking the clutch might be contaminated and causing the early engagement; although it does not slip.

Going to brave it and drive it today to Road America.
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Old 08-18-2012   #27
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Default Re: clutch engagement; early

This is a full marce,non-spriung, disc; not the one that ends 1" before the edge
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Old 08-18-2012   #28
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Default Re: clutch engagement; early

Floor mat not the issue, I have been sliding it back to check
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Old 09-22-2012   #29
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Default Re: clutch engagement; early

This has to be the the master; the pressure in the 92 kicks in earlier and I would think that has to be the master not creating pressure
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Old 09-22-2012   #30
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Default Re: clutch engagement; early

Quote:
Originally Posted by LGAFF View Post
This has to be the the master; the pressure in the 92 kicks in earlier and I would think that has to be the master not creating pressure
I got to thinking about this today and some thing that happened to me shortly after buying my car in early 97.

I took the car into city traffic up in Seattle. I was in a lot of stop and go.
Lots of up hill stops where to get going there was a lot of clutch slip.
When I got onto the freeway back to the Portland area I didn't change gears. By the time I entered traffic again and pressed the clutch in the clutch plate and pressure plate had fused. I pressed hard repeatedly to get the clutch in. Well long story short, the clutch plate finally separated and I noted the clutch peddle engagement position had changed.
After cleaning the bell housing out and lubing the pivot ball I noticed the clutch fork was bent. I straightened it, put in a new clutch plate and all was good and has been for all these years.
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Last edited by scottfab; 09-23-2012 at 12:49 PM.
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