Hello all,

First, I have searched my fingertips off about this issue and haven't found much.

My car is a 66 Chevelle, with a LSX376, T56 Magnum (new aftermarket), and LS7 clutch/plate/flywheel. I used the GM 98-02 hydraulic throwout / slave cylinder and a master cylinder from Keisler.

The symptom I'm having is the clutch won't engage entirely. Notice this is opposite of what most threads are for - people with clutch that won't DISengage entirely. This is why I am starting this thread.

I know the clutch is installed correctly and torqued right with no clearance issues on the bolts - I read about those issues beforehand and checked obsessively and I am certain neither of those things is my issue.

I am not leaking fluid anywhere and my clutch is bled and the pedal feels strong, definitely not spongy at all.

The car acts like the throwout bearing/slave cylinder is too big - like it is keeping the clutch disengaged even when the pedal isn't being pressed. It will move itself but the clutch only starts to catch at about 1/4" from the top of the pedal travel. One other odd thing is the clutch doesn't pop up from the floor very fast like my 09 Z06 did (I was expecting this to feel very similar since the clutch and pressure plate are the same).

I am planning to remove the trans tonight and take a look to see if anything is obviously wrong. I read once or twice that overextending the slave cylinder will mess up the pressure plate fingers and cause a loss of grip. I don't know if there is a way to measure for the fingers' position to see if this has happened.

I really hate to blindly go buying a new clutch/plate (apparently plate is not available separately assuming that is where my failure came?) or slave (assuming it is not overextended or damaged) since everything is brand new already.

Any ideas or direction to look for issues would be helpful. I will be measuring the A and B dimensions mentioned in Tick's helpful thread to see what clearance I have between the plate and throwout bearing. One reason I went with the GM plate/clutch/slave was to avoid having to shim and do all that but I figure I will measure anyway.

I appreciate any help you guys may have.

 

Is the master cylinder pushrod adjusted correctly?

 

You called it! I actually went and checked that this afternoon and it was hard tight against the pedal stop so I re-adjusted it and it works much better now.

I am pretty sure I did some damage to the pressure plate by pushing so hard against it, but it is still functional at this point. If I find it doesn't hold enough, I will probably just put a Tick adjustable master and new clutch/plate combo and all that. I definitely need to relocate the clutch pushrod point on the clutch pedal to get the pedal to have a more normal swing to it.