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As some may have seen, I am resurrecting a 72 Pantera that was in storage since 1990. Starting of freshening the brake system, but the clutch system may have an issue. The pedal is VERY hard. While waiting for parts to show up for the brakes, I will turn to the clutch hydraulics.

I own a 1970 Triumph GT6. Occasionally, after a long "sit", the clutch can "stick". Being a hydraulic system, there is a method of freeing it and all is again good, but the issue is mechanical. Anyway, it is my understanding the the clutch system can freeze up as well on the Panteras. Assuming the master and slave are okay, what is happening in the bell housing to cause this?
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Moisture possibly corroded the clutch disc to the pressure plate or flywheel is all I can think of? All you have in there is the flywheel, disk, pressure plate, t/o bearing, and pilot bearing. Slave cylinder is external so you may want to detach it's linkage from the pivot arm that drives the t/o bearing and have someone else push the clutch pedal to see if the slave is working or if you have leaks in the hydraulic components? You can also look down in the bell housing through the dust cover opening. I know when I would detail my engine if I got water in the bell housing the clutch would stick at first but it free'd up after pushing the pedal or rolling the car in gear back and forth and then I would let the motor run until the residual moisture went away. Good luck!
Yes, I agree with this.

The hydraulic part of the system is pretty self reliant.

It doesn't take long for the clutch disc to freeze to the flywheel.

I've noticed this on mine often. Best to get in the car and not only run it but work the controls also.

The clutch will usually pop free by itself with a few applications but I think this is likely what you are experiencing.

The special Pantera disc has no Marcel built into it. The Marcel is what breaks the disc free from the flywheel and pressure plate upon full travel.

This is one of the pitfalls to not having Marcel in the clutch. If you don't know what Marcel is, you can Google it. There is online explanation of it. M
quote:


The special Pantera disc has no Marcel built into it. The Marcel is what breaks the disc free from the flywheel and pressure plate upon full travel.

This is one of the pitfalls to not having Marcel in the clutch. If you don't know what Marcel is, you can Google it. There is online explanation of it. Most never think about it at all.


Is it some sort of built in spring plate? If so, a plate either has it or not. So, how is one to know before purchasing a clutch? Knowing how "knowledgeable" most parts people are, I can just envision the blank stares when asked.
If money is tight and you can not afford a Cenerforce Clutch kit or one from the vendors then pull your old parts and try to find a parts store that the guy at the counter will let you see parts from mustangs, ranchero's, and trucks from the early 70's. you should be able to find what you needed if you have the stock flywheel. I think they were just ford truck clutch compenents however I am sure someone else will chime in and correct me if I am wrong. The slave is an old Chevy one from what I recall? I have the Centerforce flywheel and pressure plate and when my disk wore out Centerforce would not just sell me the new disk although the other components were fine. I found a disk for a Mustang at Kragen Auto that has been in the car 10 years now and works just fine for $50 bucks and it is lifetime Smiler. It takes some effort but well worth it. Centerforce wanted another $1,000.00 for a whole new clutch kit and F that!
It is hard being the Professor but forgetting stuff is part of it.

Marcel is the spring that is built into the center disc that pushes the inner side away from the outer side. When you look at the disc from the edge, it is s shaped. It is not Marcel Marsou.

The clutch in a Pantera IS NOT A MUSTANG CLUTCH. It is unique to the Pantera. That's why it's all by itself in the parts books.

It is different because the amount of travel that is available from the hydraulic slave cylinder is inadequate to use with the Mustang unit.

They played with this in the beginning and rather then reinvent the wheel the simplest thing was to modify the center disc to gain the travel needed.

To the unknowing, at first view, people will think it is the same as the Mustang.

If you try the Mustang, which does bolt up, you will find that you can't get the extra 1/8" or so of travel that the throwout bearing needs to fully release.

If you want to go that way i just have this to say, the synchros in the ZF are $900 each, and you need 5 of them. Your choice. Not my problem. Wink
"The clutch in a Pantera IS NOT A MUSTANG CLUTCH. It is unique to the Pantera. That's why it's all by itself in the parts books."

Perhaps this above mentioned is true and I am no engineer and only sharing my experiences.

Everyone has a opinion and in my case I am using a Centerforce Pantera specific flywheel and pressure plate. The Mustang disk I have been running for 10+ years works great for me with those Centerforce components. I don't race my car and use it for pleasure only. Also I ran the ideal by Bob and Don Byers from Precision Proformance before I did this and they inspected my pressure plate and disk. Since they are or were Centerforce dealers back then I thought they could get me the disk. Centerforce would not sell Bob just a new disk to sell me and Don said the magic in the Centerforce Clutch is the pressure plate and they said go ahead and try the Mustang disk and to report back.

I installed the clutch, drove it to Don and he checked the free play adjustment and away I went.
quote:
Originally posted by Lousbby:
"The clutch in a Pantera IS NOT A MUSTANG CLUTCH. It is unique to the Pantera. That's why it's all by itself in the parts books."

Perhaps this above mentioned is true and I am no engineer and only sharing my experiences.

Everyone has a opinion and in my case I am using a Centerforce Pantera specific flywheel and pressure plate. The Mustang disk I have been running for 10+ years works great for me with those Centerforce components. I don't race my car and use it for pleasure only. Also I ran the ideal by Bob and Don Byers from Precision Proformance before I did this and they inspected my pressure plate and disk. Since they are or were Centerforce dealers back then I thought they could get me the disk. Centerforce would not sell Bob just a new disk to sell me and Don said the magic in the Centerforce Clutch is the pressure plate and they said go ahead and try the Mustang disk and to report back.

I installed the clutch, drove it to Don and he checked the free play adjustment and away I went.


I'm not arguing. I am running the Centerforce Pantera specific clutch also.

I don't argue with Bob since he is one of the Pantera alchemists out there. They certainly have done a lot more Pantera clutches then I have. Wink

I'm merely trying to explain why the Pantera clutch is different.

When I got my Pantra it had less then 100 miles on a new clutch. It had a Mustang unit in there and was grinding 2nd gear pretty badly.

I have Centerforces in my two Shelbys. A 68 GT350 with Doug Nash 5 speed behind a 347 and a 67 GT500.

The 68 has an alchamists clutch in it too. It is an 11 Chevy fine spline. The critical thing for it is to set it so it has a minimum clearance cold of .045"

A diaqphram clutch, which the Centerforce is, needs more clearance then the three finger Ford does. It needs more then a minimum of about .035" clearance that the Long does. It needs .045.

IF and the Devil is always in the details, you can get .045" clearance at full travel in a Pantera I'm sure that you are ok.

You have to do this with a feeler gauge from the edge of the clutch assembly and with the Pantera Bell, I don't know how you measure it.

Not to be a pencil neck about this, but if you can get the Mustang to work, then you probably are ahead of the game. I couldn't. Maybe there is a trick to it.

In defense of pencil necks everywhere, it is best to recommend what the "book specifies". If one can invent a solution, it usually re-writes the "book" anyway. That's called progress or sometimes technical inovation.

It may also be that the recommendation was so they could use an 11 inch disc instead of the 10.5 that is the disc in the Pantera specific unit.

I yield to the greater authority. Smiler
Comparing the original Ford long clutch and pressure plate to the Centerforce is like comparing apples to oranges. They are two different animals (or should I say fruits Smiler).

As I recall, the Centerforce is 10 1/2" and requires their flywheel (or redrilling of the stock Ford flywheel). The original Ford Pantera clutch is 11".

McLeod has a Pantera specific 11" clutch disc.

Clutch disc: #260131
Pressure plate: #36050

John
I can tell you, back in the day, before I knew anything about Pantera's, I made the mistake of buying a Mustang clutch for my Pantera. I only had the car for a couple of months and was installing a new motor and clutch.

So after the long rebuild process, smoothing the engine compartment, re-installing everything, I was excited to get her back on the road.

To make a long story shorter, I got in the car and could not put her in any gear when running. I shut off the car, put her in gear and attempted to start the car with the clutch in. The car lurched forward. The clutch felt normal to my foot.

Come to think about it, I purchased the Mustang clutch because I thought the price the vendors wanted for a clutch was ridicules. I still think that, by the way. And I thought to myself, what could be different. So I went ahead with the purchase of the Mustang clutch from Summit.

So now I can't drive the car, crap. what-to-do, what-to-do...

I made a call to Pantera East and ordered a long throw slave cylinder, installed that puppy and ran the car for years with any issues whatsoever.

So, in the end, Yes, they are different. BUT, one can get the Mustang unit to work...
SNAPONBOB,
Have you ever driven a Pantera before? When I first got my Pantera a couple years ago, I went to push on the clutch pedal and swore something was wrong. The pedal was extremely stiff. I just got used to it. It's much stiffer than your typical modern clutch pedal.

For reference, My car is a 72 and it does not have the clutch effort reduction linkage. My car also is using a McLeod 1400 series throwout bearing.

John
quote:
Originally posted by mistersolo:
SNAPONBOB,
Have you ever driven a Pantera before? When I first got my Pantera a couple years ago, I went to push on the clutch pedal and swore something was wrong. The pedal was extremely stiff. I just got used to it. It's much stiffer than your typical modern clutch pedal.

For reference, My car is a 72 and it does not have the clutch effort reduction linkage. My car also is using a McLeod 1400 series throwout bearing.

John


1) Checked, and the hydraulics are working.
2) Not "frozen". Phew.
3) Never driven one, but SOON I expect to say I have !!
4) Owner recalled it being not as heavy, but is now 70ish, and has not driven it since 1990. Memory may have failed. Big Grin
5) I plan on looking into a clutch effort reduction linkage.
Besides what JB and Doug said, the Pantera's Long-type clutch assembly has NO centrifugal assist weights built in. Mustang, Fairlane & truck units do. The weights swing out at idle speed and smash into cast aluminum reinforcing ribs inside the close fitting bellhousing. The sound will stop your heart! If it doesn't crack the bellhousing, you are a lucky puppy.
Second note: Centerforce clutches use a different bolt pattern and larger thread bolts with stand-offs. They will not bolt onto your stock flywheel. There are reasons why Pantera clutches are expensive....There are also shops that will rebuild your stock clutch assembly to any holding power or foot pedal pressure you desire. You will need to bring the OEM parts in, though. It will likely cost the same as a new clutch from a recognized supplier.
To permanently cure clutch-plate sticking, either drive the car every day for a considerable period, or pull the ZF and sand the clutch, flywheel and both sides of the clutch plate. Long-throw slaves are an excellent addition to any Pantera; gear grinding indicates lack of throwout travel. It wears out the ZF synchros each time you change gears, and replacement cost of the parts involved is in the thousands of dollars!
quote:
the Pantera's Long-type clutch assembly has NO centrifugal assist weights built in. Mustang, Fairlane & truck units do. The weights swing out at idle speed and smash into cast aluminum reinforcing ribs inside the close fitting bellhousing. The sound will stop your heart! If it doesn't crack the bellhousing, you are a lucky puppy.
Second note: Centerforce clutches use a different bolt pattern and larger thread bolts with stand-offs. They will not bolt onto your stock flywheel. There are reasons why Pantera clutches are expensive


I RESPECTFULLY disagree with you on this topic.

The clutch I purchased for my Pantera was a Centerforce II Mustang Clutch (with assist weights) that bolted up, no problem, to my stock Pantera flywheel.

There are reasons the Pantera clutches are expensive agreed BUT, to say that an inexpensive clutch won't work or is somehow going to damage the ZF is not my experience. I ran that setup for 4 years.

If the potential clutch purchaser wants a no issue install and has plenty of money, then I agree to go with the Pantera specific clutch. But if the same person is on a budget, then the Mustang clutch, properly installed with a long throw slave will work just fine...

Again, I say this with the utmost respect intended BOSS, as I respect you and your extensive knowledge on these wonderful cars.

Scott
The only thing that changes here is the long throw slave cylinder. Apparently with it you CAN use a Mustang DIAPHRAGM clutch. That's a good thing, but it will only fix the travel issue, not the clearance issue of the wrong Long clutch not clearing the ZF bellhouse.

With the standard slave everything stated about needing a Pantera clutch is accurate.

Personally I'll be buying one ASAP. Does Pantera East have an on line presence and catalog?

Thanks for sharing your experiences Scott, that helps.



Incidentally my Centerforce Pantera clutch does have the counterweights and I haven't experienced any issue with them as of yet.

My understanding of how they work is that at idle they are doing nothing but as rpms rise and the centrifugal force moves them outward, they apply more clamping force to the clutch fingers?

I've never seen a graph or data sheet on this effect from anyone but I'm sure there is one around somewhere on the net?

The only number I heard about the Centerforce is that "the racers", and they know who they are, say the clutch is good for around 800 hp.

One thing that I did notice with the Centerforce is that around 6000rpm the pedal gets very hard. In my GT350 it will push the pedal up. The Pantera I haven't noticed that most likely because of the hydraulics.



As far as what Bosswrench is saying about the original Pantera clutch having no counter weights, I agree with him. I think he was refering to the Long style and not the Centerforce diaphragm type though.

He is referring to the little "dumbells" on the short end of the three arms on the clutch cover. They wouldn't clear the inside of the ZF aluminum bellhousing, using a normal Mustang clutch cover (pressure plate) or any other Ford Long clutch for that matter.

The Pantera long clutch doesn't have them. It uses different lever arms.

If you attempt to use the "long" clutch from a Mustang, unless the bellhouse has been clearance internally for them, there is going to be some serious internal collisions, with a lot of disgusting internal noise, followed by a lot of crying over broken parts.

Using a long throw slave cylinder won't save you on that.

But this only pertains to Long clutch, not the Centerforce diaphram type.



There are always people that complain that they are new and need information. When the experienced "old" guys give it to them, then they turn and complain that the old guys don't know what they are talking about. Ironic isn't it.

In my case I have always tried to listen to them. I learned that they are not necessarily highly intelligent, just highly experienced. Your mileage may vary.



Cavete emptor. Wink
Last edited by panteradoug
quote:
As far as what Bosswrench is saying about the original Pantera clutch having no counter weights, I agree with him. I think he was refering to the Long style and not the Centerforce diaphragm type though.

He is referring to the little "dumbells" on the short end of the three arms on the clutch cover. They wouldn't clear the inside of the ZF aluminum bellhousing, using a normal Mustang clutch cover (pressure plate) or any other Ford Long clutch for that matter.

The Pantera long clutch doesn't have them. It uses different lever arms.

If you attempt to use the "long" clutch from a Mustang, unless the bellhouse has been clearance internally for them, there is going to be some serious internal collisions, with a lot of disgusting internal noise, followed by a lot of crying over broken parts.

Using a long throw slave cylinder won't save you on that.

But this only pertains to Long clutch, not the Centerforce diaphram type.


Thanks Doug, that makes sense. Boss must have been talking about the long style clutch. Of course, as you pointed out, my comments were surrounding the Centerforce diaphragm type clutch.

So I still stand by my comment that an inexpensive Mustang clutch is available and works just fine with a long throw slave. I think we are agreeing on that point. I knew this day would come... Big Grin

So my question is this, Why would someone want to go with the long 3 finger design over a diaphragm design. I hope the answer isn't that they will hold more power because I don't think that is the case. And my experience with the 3 finger long clutch is that they are way harder from a peddle pressure perspective. I am confused as to why one would want to go that direction???

Scott
quote:
Originally posted by ZR1 Pantera:
quote:
As far as what Bosswrench is saying about the original Pantera clutch having no counter weights, I agree with him. I think he was refering to the Long style and not the Centerforce diaphragm type though.

He is referring to the little "dumbells" on the short end of the three arms on the clutch cover. They wouldn't clear the inside of the ZF aluminum bellhousing, using a normal Mustang clutch cover (pressure plate) or any other Ford Long clutch for that matter.

The Pantera long clutch doesn't have them. It uses different lever arms.

If you attempt to use the "long" clutch from a Mustang, unless the bellhouse has been clearance internally for them, there is going to be some serious internal collisions, with a lot of disgusting internal noise, followed by a lot of crying over broken parts.

Using a long throw slave cylinder won't save you on that.

But this only pertains to Long clutch, not the Centerforce diaphram type.


Thanks Doug, that makes sense. Boss must have been talking about the long style clutch. Of course, as you pointed out, my comments were surrounding the Centerforce diaphragm type clutch.

So I still stand by my comment that an inexpensive Mustang clutch is available and works just fine with a long throw slave. I think we are agreeing on that point. I knew this day would come... Big Grin

So my question is this, Why would someone want to go with the long 3 finger design over a diaphragm design. I hope the answer isn't that they will hold more power because I don't think that is the case. And my experience with the 3 finger long clutch is that they are way harder from a peddle pressure perspective. I am confused as to why one would want to go that direction???

Scott


I don't know which clutch type the McLeod is. Other then a rebuilt stock, there are only three types available at the moment. Centerforce, McLeod, rebuilt stock.

I agree with you Scott, the diaphragm type is much more user friendly.

Using a Long is just a step backwards, not ahead.

Hopefully this discussion will help a novice make an informed decision on a new one.

I certainly learned something new with the long throw slave. It's definitely on my to do list now. Smiler

We agree a lot more then you think.
The two long style pressure plate photos illustrate an interesting point.

John's photo illustrates how Ford modified their long style pressure plate by cutting off the weights at the end of the levers in order to clear the bell housing.

The McLeod clutch in Doug's photo retains the weights on the ends of the levers ... they get away with this by designing a Pantera specific pressure plate that mounts the levers 0.100" closer to the flywheel (compared to their standard Ford pressure plate) to gain the clearance needed to allow the weights to miss the bell housing. The aftermarket clutch retains the advantage of the weighted levers.


-G
I can see where you could cut off the counterweights on a Mustang clutch cover but you do realize that the thing needs to be in balance don't you?

My idle's a little rough but it's from the cam profile, not a dum-dum clutch? Roll Eyes

I see the offset now George. I suppose I would need them side by side to have noticed that right off?

I'm wondering though how this effects the leverage and thus the pressure and the feel of the clutch pedal? I don't think it can be good. It isn't going to make the clutch feel any lighter?

The Long is not the way to go under normal conditions. Even there it is a heavier clutch then the diaphragm.

Even so, it is a tricky solution by McLeod.
Last edited by panteradoug
I had assumed McLeod had to modify the pressure plate to account for the thicker disc with the Marcel in it. Had no idea it was so the weights would clear the bell housing. Is the modified McLeod PP why they want you to use their adjustable throw out bearing?

Has someone already posted how to make the measurements and adjust the TOB? Mine did not come with any instructions. Thanks
I think it is important to mention that the discussions about the original clutch are now really academic.

If you are still running it, then it is working and you don't need to do anything to it until you replace it.

There are no stock replacements from Ford still available to my knowledge. They went the way of the Doodoo bird over 35 years ago.

The discussion is really what choices you have to make now. The kits from Centerforce and McLeod are set up ready for you to install. Follow their instructions.

If you choose to go the route of modifying a Ford Mustang family clutch, THEN and ONLY THEN do you need to do things like on a Long three finger type, clearance it for the bell house, and install a long throw slave cylinder.

I'm amazed that I already got a PM from an engineer that doesn't know the difference between a Long and a diaphragm stile like the Centerforce.

Google these things fellas. If you are relying on me to be your Dally Lama you are in deep trouble.

These cars are very specialized in many areas and you need to know how to do more then just change the oil, turn the ignition key and fill it with gas. You do know how to do that right? Right? Hello...anyone there?

Yikes! That's what I thought? Eeker
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