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Marc Haibeck · 08-18-2012

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.

08-18-2012	#24
Marc Haibeck Join Date: May 2007 Location: Addison IL Posts: 254	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.