I have got a doozy here and I cannot figure it out. Two and a half weeks ago, I went on vacation and drove a different car than my Formula. When I got back and started driving it again, it all of a sudden felt like the clutch had worn a lot while I was gone, but it had only been driven 100 feet to the shed by my father while I was gone. It was disengaging clear at the top of the clutch pedal stroke (whereas it had been in the middle beforehand).

I drove it this way for two weeks, biding my time till I get a few paychecks at my new job so I could replace the clutch. I get in the car to go to church one day after said two weeks and the clutch feels like it's disengaging in the middle again like it had before. I get out of church and the clutch is back to feeling worn out and disengaging at the top of the stroke.

The next day, on my way to work, the clutch starts disengaging clear at the floor, and not disengaging all the way at that. I limp to work, limp home, and figure it is the master cylinder (the slave cylinder was replaced six months ago by a professional shop). The MC is a 1st gen McLeod unit (the one made by CNC brakes). I ordered a rebuild kit, honed the cylinder to smooth it out, and rebuilt it. Got it installed and bled today and the clutch is back to the way it was, barely disengaging and at the bottom of the pedal stroke.

Now both before the MC rebuild, and now, the pedal resistance is odd. There are three different resistances throughout the stroke. At the top of the stroke is free travel, I imagine taking up the slack in any linkage. This has always been there. Next, there is increased resistance like I'm hitting up against the spring in the master cylinder. Finally, there is another increase in resistance like the clutch is finally trying to disengage.

The odd pedal resistance leads me to believe that it is something inside the bellhousing that is wrong. It's like the slave has a ways to go before it hits the pressure plate or something. Can a slave shim just randomly fall out?

If anyone has any advice, please let me know. I would greatly appreciate the feedback.

 

Have you tried bleeding it? A shim can't fall out, feel free to call me and discuss further. Chris, 817-750-2000

 

I bench bled the MC, put it on, and then used the "Mityvac in the reservoir" mentioned several places in this forum. When I got home today, I disconnected the line from the slave cylinder and pushed on the pedal. It was rock solid, telling me there is no air in the MC or the line down to the slave. Then I bled the slave using the traditional method of having a friend push in the clutch, opening the bleeder, closing the bleeder, and pulling up the clutch. I never heard any air come out, but bled it quite awhile anyway. I was also very sure not to let the reservoir run dry. This did not fix my issue.

So it must be something messed up inside the bellhousing after the slave. The previous owner had a double disc clutch put in it and that is still in the car. Idk what brand it is. So what mechanical part inside the bellhousing could be causing the clutch to not disengage?

 

If the clutch isn't releasing but nothing has changed relative to use because the car hasn't been used then there really isn't much that could be wrong with the clutch itself. This is still most likely a hydraulic issue. You may be seeing bleed-by within the slave or master that is reducing the amount of hydraulic pressure that actually makes it to the bearing and subsequently the diaphragm fingers. Disconnect the line that runs from the master to the slave. Then lightly apply pressure to the pedal. If the pedal drops then you are seeing an issue with the master.

 

I'm not totally sure what you're trying to say at the beginning of your post. This changed happened while I was driving it one day. This is my daily driver car, so it was being used every day when whatever happened, happened. The master cylinder is tight. In the post just above yours, I said that I disconnected the line from the slave cylinder and the clutch pedal was rock solid.

The reason I've ruled out the slave is because it was replaced 6 months ago. Yes, I'm aware it could be bad, but at this point, it's something in the bellhousing and I'm going to have to take out the transmission to fix whatever it is anyway. I'm just trying to narrow it down to what it could be so that I can order parts and have them handy when I get around to dropping the tranny.

 

If this is a stock clutch it could be the self adjusting fingers in the diaphragm spring causes a problem, let us know what you find out.