Why is the Clutch Peddle Sticking?

[Xavier]

This issue just popped up last weekend, car had to be grounded. Issue is the clutch peddle sticks, it happens far more in gears than out of gear which does not make that much sense to me. No noise. You just push in the clutch, and when the clutch peddle rises it is choppy either that or it does not raise completely and then suddenly does causing the unsafe tire squeal and brief loss of control. Pushing the peddle down you can sometimes feel the chop, sometime not.

I have a TKO 600 with a Center Force clutch, McLeod HTB with a Tilton MC.

Fluid looks good and is all there.

All I can come up with is;

A- The HTB blew, seals went. If the seal went shouln't it be leaking? Why no loss of fluid?
B- The MC went - seals blew making it choppy. I have a hard time imagining this.
C- Something wrong with the clutch diaphram. But what?

Why all the sudden?

[jhv48]

Your assesment is correct. Sounds like a bind in either the HTB on the bearing retainer or the pressure plate itself could have one of the springs going out and is thus binding. I can't see the master cylinder causing this, but it is by far the cheapest and easiest piece to replace first.

So, if you are a gambler, start replacing one piece at a time and hope that was it. Start with the M/C first, it's the easiest but least likely. The HTB or the pressure plate is my guess.

If it were me, and it recently was, I would pull the tranny and examine the pressure plate and the HTB. Especially check the part of the HTB that slides on the bearing retainer from the TKO. Specifically, look for any marring of the metal finish on both the retainer and the HTB. If it is not perfectly smooth inside, replace it and the retainer. If neither shows any marks, then replace everything from the pilot bushing/bearing to the HTB. Otherwise you might miss the problem and will have to do it again.

Good luck.

[Jaydee]

It could be some of the diaprham fingers have broken of , and cocking the throw out bearing, jamming it on the shaft. Especially if the grease has dried up on the shaft. Will it jam without the engine running? If so, work the clutch until it jams, then loosen the bleed nipple on the slave, if the clutch jumps back, then the mc is jamming.
JD

[Morris]

Are you going over center on the clutch diaphragm??????

[Xavier]

Thanks for the replies. Morris, please explain over center, since I don't know what it means it most likely means I have it wrong...I believe you mean is the HTB going too deep into the plate. Can't recall what the setup was, but what I remember in the instructions was that the HTB was to be out a certain distance off the TKO housing, as this distance was easily clockable as an adjustment. Once you had this distance the stroke of the HTB was to be adjusted by the clutch pedal which is why you had to have an adjustable stop. I did that and I do not think it is physically possibly for it to change.

Right now I think the best bet is get the car on stands and while someone is engaging the pedal for the clutch, blow everything out with and air gun and put my hand inside to feel the fingers on the diaphragm and sense the movement of the HTB. See where and when it is coming off choppy. As JD suggested I could at least feel the diaphragm fingers.

I think the tranny is going to get pulled out sooner or later with this problem. As I recall, the HTB can be rebuilt from McCleod? Not sure. If its reasonable to get rebuilt, as I have the tranny off, I will get it rebuilt regardless.

Man, wouldn't it be great if it were just a bunch of clutch dust on the input shaft? What am I thinking??? Nothing ever goes easy or cheap on this car...

[Jaydee]

You shouldn't adjust the clutch at the pedal. The mc always has to come back to the stop. You can only adjust it at the slave, until the freeplay is taken up. If you adjust the pedal, the fluid can't flow back into the resevoir, and you will end up pumping the slave until It either pops out, or you push the bearing through the fingers.
JD

[jhv48]

Originally Posted by Jaydee

You shouldn't adjust the clutch at the pedal. The mc always has to come back to the stop. You can only adjust it at the slave, until the freeplay is taken up. If you adjust the pedal, the fluid can't flow back into the resevoir, and you will end up pumping the slave until It either pops out, or you push the bearing through the fingers.
JD

A hydraulic throwout bearing has no slave cylinder to adjust. Clutch adjustment must be at the pedal. Not your solution though.

[Xavier]

HTB = Hydraulic Throwout Beaing (no slave).

Yeah, I just read the instructions again from long ago. There is a set distance from the face of the HTB to clutch at .100 to .125. From there you are to park the car on an incline press the pedal and set maximum pedal movement once car starts rolling, set your stop at that point to not over extend HTB as this is the result a tech told me at one time results in almost all HTB failures.

Also I did not put grease on the input shaft as the instructions stated, contrary to what many told me, in large bold type "DO NOT USE OIL OR GREASE" only use DOT 3 brake fluid to slide the HTB on the shaft.

Again, that is not the problem as it has been running flawless like this for years, but if the fingers DID break, I would like to know why.

[Jaydee]

So when you say adjust at the pedal. you mean you let the pedal come up higher, or, you are in effect pushing on the rod, so the mc doesn't bottom itself out. I have seen slave cylinders with screw adjustment. You let the cylinder bottom out, adjust the rod with a bit of slack. So you get maximum travel.
JD

[xlr8or]

If you have the center force pressure plate with the weights on ring around the clutch fingers it sounds like maybe that is coming apart.

[Xavier]

Jaydee, you are referencing a hydraulic slave, I have no slave, no fork a throw out bearing that is engaged by pedal hydraulic. You have to limit the pedal movement as to NOT blow out the hydraulic bearing seal as it will over extend. The benefit of the HTB is simplicity, the downside is if something fails you have to pull the tranny.

Xlr8or,
When purchased, after looking at the design when new, I considered the strengths and weaknesses of the weights you refer to and removed them. The benefits did not out weigh the weakness in my opinion, and never regretted taking them off after talking to Center Force. Just one less thing to fail.

I will look at it this weekend, just hope it's not th clutch diaphragm.

[JustOne]

The same thing happened to me, theMcCleoud HTB was coming apart. If you do not pull it out soon you will be purchasing a new pressure plate as well.

Justin

[Xavier]

Thanks Justin. I am pulling the tranny this weekend.