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My clutch engages near the top of the pedal travel, I want it much closer to the floor, can it be anything else bedsides a worn clutch? Just got the car, reads 17k miles. Shifts fine.

Also, On the slave adjustment, after I think I've got it set right, I go for a drive. when I recheck it, it seems I've lost my free play.
I would love it if somebody could do a comprehensive YouTube video on this adjustment. I've read everything there is to read and still confused. References to items that are not familiar to you do little to aid in understanding. I'm doing all my adjustments through the plunger. I don't see how that little screw and stop nut do anything.
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You need to make the adjustments per the pic below.

Adjust the slave cylinder pushrod to the length shown and reinstall.

Adjust the free play (at the stop bolt) to the dimension shown. It's easier to adjust with the spring removed.

Make sure that the spring is strong enough to allow the clutch arm to return until the end of the adjusting bolt contacts the metal stop bracket.

John

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I am very familiar with those instructions. I cannot get there. If I rotate the arm on the spline (blue arrow)close enough to get that .102 gap, the pushrod has to be adjusted so far in, there are no threads showing and it's jammed into the cylinder no way to get any free play.

If I move the arm on the spline back, the screw is not long enough to get near .102 mark. It's not possible on my set up and it's all stock.

Is the .102 gap with the arm pulled back or at rest?
quote:
Is the .102 gap with the arm pulled back or at rest?

It is measured with the clutch arm pulled back (toward the rear of the car). It's much easier to do with the spring removed.

Replace the adjusting bolt with a longer one.

When you finally get the correct free play, reinstall the spring and make sure that the stop bolt comes to rest on the stop bracket. Cycle the clutch pedal a few times and look to see if the clutch arm has returned fully against the stop. If not, the return spring may not be heavy enough.

John
quote:
I am very familiar with those instructions. I cannot get there.

I put together this simple instruction, mostly for my own benefit since this is my first clutch car.
quote:
FWIW, here’s a summary of how to adjust the clutch on the Pantera. Being used to automatic transmissions for decades, it was a new and complicated world that opened up to me when I bought a Pantera with a hydraulic clutch and especially how to adjust it. Having bought all the literature I soon found inconsistencies. I’ve read many sources including the Instruction Manual, the TSB, PanteraPlace and others. And they were quite different. I think now I finally understand how to do it, and if it can help others, below is the short simple (?) method I’ve used

First, the basics have to be right: A good master, slave, pipe and line. And a proper Pantera clutch, not just a Mustang clutch. Some recommends a long-throw slave, and that will make getting the right adjustment easier. But it’ll also increase clutch pedal effort, something you don’t want (except if you want to discourage the wife from driving ). And the fluid has to be free of air.

1. Master: pedal should be adjusted so at rest it’s between 0-½” closer to the driver than the brake pedal. Then test with a friend that with the pedal fully pressed down, there should be at least ½” gap to the firewall/carpet
2. Clutch axle arm: the almost vertical arm from the ZF to the slave rod end. Imagine a straight line from the clutch axle on the ZF up to where the clevis pin is. That line should be 90 degrees towards the slave. Ideally it should be 90 degrees when the clutch pedal is half pressed down. Any other angle will result in that the slave rod movement translates into less movement of the clutch axle. Maybe you should move it a notch? Also check that there’s free movement, when the clutch pedal is fully depressed, does the arm or the bolt/nut perhaps rub on the ZF? And get a proper size clevis pin, previous owner had just used a bolt that was 0.3mm less in diameter
3. Slave return bolt: Temporarily remove the spring. Use your hands or a tool to move the clutch axle arm rearwards, and feel for when it hits the resistance of the clutch. Should be easy to feel. While holding the arm in that position, turn the screw so that it almost touches the bracket, leaving a 2mm gap. This will ensure that a. there’s no wear on the clutch release bearing when the pedal is not pressed down, and b. that you get as much movement of the clutch as possible. Reinstall the spring
4. Slave rod: Some suggest that the rod is used to position the resting position of the clutch axle arm and that the return bolt should be thrown away. And some say this is not good, because the slave should not bottom out. I think the best is to use the return bolt as described in 3., and then adjust for almost maximum slave piston travel on the rod. Almost, so with no bottoming out. With the system at rest, take out the clevis pin and by hand press the slave rod all the way up in the slave. And then release 1mm. Do the holes now align so the clevis can be put back in? If not, adjust the length of the slave rod, so that they do

With all this done, you should have a clutch that neither slips nor grinds teeth. And of course you must press the clutch pedal all the way down every time. Happy shifting!
RSS1, the bellhousing and transaxle are aluminum and do expand considerably with heat. This changes the clearances of anything attached to the castings. Your change in free play is consistent with other Panteras, using all sorts of clutch setups. FWIW, 'free play' can be set to a bare minimum when everything is smoking-hot so it will always exist. Without any free play, the throwout bearing will always be touching the clutch arms and if it's not a constant-contact type bearing, it will wear and prematurely fail. If is IS a constant-contact bearing, and the amount of 'touch' is not very much, no problems should arise except maybe a bit of wear on the clutch arms over time. I personally do not use ANY free-play and have a constant contact bearing on a 15-yr-old annular throwout system.

Biggest problem IMHO with Pantera clutches: wnen brand-new and unworn, our systems had absolutely minimum disengagement clearance if the clutch pedal was matted. After 40 years of wear in everything, the disengagement distance is well below minimums, and adding 'free play' decreases it further.
Test: with engine OFF, have someone mat the clutch and you stick a feeler gauge thru the bellhousing hole between the flywheel and clutch disc. Spec is 0.040" and that's divided between the front & back surfaces of the disc in a running engine. 0.020" clearance isn't much, compounded by most drivers only pushing the pedal a little over 75%, depending on the synchros to match gear teeth up. ZF synchro replacement was well over $2500 last time I checked. OK- off soapbox now...
quote:
Originally posted by Bosswrench:

Spec is 0.040"


I'm not arguing, I agree, but it is important to point out that is for the Long style pressure plate and technically the diaphragm type like the CenterForce dual friction would normally need at least .045"

I want to say that I was able to achieve .048 and the throwout bearing is not riding thefingers.

This makes me think about the minimum .020 at rest though.

By comparison the Long in my Mustang would get along fine with .035 to .038 clearance at rest.

The counterweights on the pressure plate because of the centrifugal force exerted at above a certain rpm will actually push the clutch pedal up.

I'm wondering if I remembered to use a ceratmic throw out bearing when I did it? I don't remember now?

I did have a bad experience with a CenterForce dual friction in my '92 Taurus SHO. At 8,000 miles the throwout bearing had almost worn throuh the hardened sheet metal fingers.

This was curious and probably a design defect by CenterForce. The Taurus uses a constant contact throwout bearing and as I recall that part of the Ford design is not adjustable?

I'm thinking that the ceramic is also for this wear problem?
I understand heat expanding the metals, but I have a good 1/8" easy play when cold. When hot, it goes away and then some to the point the pedal is hard to initialize. Seems quite extreme. I guess I'll make the adjustment when it's hot. Of course then there will be way too much play when it's cold, and.....Oh well.
The bright side is once you have the clutch right, it stays that way.

It definitely has challenges to it.

Ever Ford product I have ever worked on, I have found the the stock clutch is by far the best.

There are no "original stock Pantera clutches" still available, so you do the best that you can.

I think what Bosswrench and I have been getting at is that is that most people didn't realize that they need to use a feeler gauge to adjust a clutch properly?
Right on, Doug. And to clarify further, I'm using a Tilton Racing annular throwout bearing assembly that encircles the ZF mainshaft, totally eliminating the cross-shaft, throwout & carrier, slave cylinder & all the linkage. Works fine and has a constant-contact bearing & long throw that gives me 0.050" clearance. Eliminating all the stock engine linkage actually SOFTENED the clutch pedal pressure in spite of more disengagement distance at the clutch. My 5'2" wife thinks its easy. The downside to annulars (besides the expense & the fact that there are none sold for Panteras or ZFs) is, if ANYTHING goes wrong, you pull the ZF to get to it for service.
FWIW, our Long clutch itself is the OEM unit delivered with our '72 L.... It's been transferred intact to two different flywheels; the disc was finally replaced in the last century but I don't remember the date. No slippage.
You can, as-stock. But that tail light panel is structural, so its not as simple as it seems. My old friend Rich didn't own an engine crane and hated to ask for help, so to change clutches & flywheels by himself in his track Pantera, he unbolted the AC condenser & laid it over the rear fender on a towel without undoing the pressurized lines. Then he unbolted the ZF & bellhousing, and slid the package back about 8"- enough to get in there with a ratchet & torque wrench. He did a single-handed clutch and one flywheel change in the '80s this way.
Structural, yes, I know but in looking at it, driveline was the least consideration of the car I think.

You can plumb in a couple of shut off valves at the condenser so that you don't loose all of you're coolant when you disconnect it. Since I went to 134a I don't worry about a couple of cans of it.

Sliding the ZF back is what I do also. It just barely makes it clear enough. Helps alot on the re-installation though.

I hate asking anyone to help on a transmission installation. All they do is piss and moan and then get greasy hand marks all over everything. I just throw everyone out and lock the door. When everyone sees the white smoke coming out of the chimney, they know that I have a new clutch. Big Grin
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