Clutch adjustment?

correct...
(Just rounding things in my head)
but,
why get exact now?

quote:

Originally posted by Peter Fenlon:
the actuating arm is at the rearmost position, there is no adjustment left on the rod to enable another spline to be reached

Hi Peter,

I don't understand that statement, the clutch arm is infinitely adjustable on the splines (within the bounds of the ZF casing) as it has a through bolt and the shaft is machined in it's full circumference. The actuating rod looks to be at it's shortest with no threads showing after the locknut, so could be lengthened?

Julian

quote:

Originally posted by Joules:

quote:

Originally posted by Peter Fenlon:
the actuating arm is at the rearmost position, there is no adjustment left on the rod to enable another spline to be reached

Hi Peter,

I don't understand that statement, the clutch arm is infinitely adjustable on the splines (within the bounds of the ZF casing) as it has a through bolt and the shaft is machined in it's full circumference. The actuating rod looks to be at it's shortest with no threads showing after the locknut, so could be lengthened?

Julian

Hello Joules,
I meant that I could not reach another spline
in the forward direction (toward the slave cyl)
in lots of pics I see only about 4 threads in front of the slave cyl locknut. Bringing the lever arm rearwards would be easy, but the length of the rod is then much longer.

The lever arm is now I think in the correct place, i.e. just forward of "Centre" so the arc of travel is at its most economic, and no movement is lost.

I wish I could post some pics but am having "Bucket" problems.

Peter,

I still believe you may need to be one spline further back (away from the slave) and the rod lengthened, but let's approach it more scientifically, how long is your clutch slave rod? The TSB is fairly precise in that it should be 3.07 to 3.09"

What I have also encountered is the ridged barrel on the rod where the rubber boot sits is slightly larger than the slave bore and can bind up against the slave if the slave piston retracts all the way back impacting clutch operation. This could also be why you currently cannot dial in any free play.

Julian

Photo of clutch arm relative to slave;

As you all can probably guess I am thoroughly cheesed off and all the suggestions however well meant, will not give me half a millimetre between the clutch and flywheel and another half millimetre between the release bearing and the 3 clutch fingers.

My new longer throw slave is due on friday, so I shall fit that and go from there.

As yet no one has mentioned the reason why a longer throw slave IS available, and if the stock system is so easy to utilise why do so many dealers stock the LTSlave cyl????

I have had all spline options tried out with the actuating arm.
tried several bleeding methods vacuum etc etc.
pedal box out twice, changing the Effort reduction kit geometry.

changed back to standard master rod, dropping the ER Kit altogether.

Taken the gearbox out twice, fitted the correct parts eventually.

It was my fault I had the old spinner relined
I had no idea that it was a special item.

Fingers crossed , but thanks to all those who have contributed, best Peter.

I have empathy in your delemia, as in what has changed

I understand your actual slave stroke is not what is calculated based upon info I gathered from the internet. and the couple of members that were gracious enough to share their stroke makes it even more confussing

while waiting for the LT slave, have you attempted to measure the arm travel that will be needed to provide ToB clearance to plate clearance.

I could envision that different clutches would require increased arm strokes and thus the reason for the LT slave.

I am also waiting impatentaly for your resolution

If I had another 1.5mm I would be laughing teacakes.

Pete.

quote:

Originally posted by Peter Fenlon:
As you all can probably guess I am thoroughly cheesed off and all the suggestions however well meant, will not give me half a millimetre between the clutch and flywheel and another half millimetre between the release bearing and the 3 clutch fingers.

My new longer throw slave is due on friday, so I shall fit that and go from there.

As yet no one has mentioned the reason why a longer throw slave IS available, and if the stock system is so easy to utilise why do so many dealers stock the LTSlave cyl????

I have had all spline options tried out with the actuating arm.
tried several bleeding methods vacuum etc etc.
pedal box out twice, changing the Effort reduction kit geometry.

changed back to standard master rod, dropping the ER Kit altogether.

Taken the gearbox out twice, fitted the correct parts eventually.

It was my fault I had the old spinner relined
I had no idea that it was a special item.

Fingers crossed , but thanks to all those who have contributed, best Peter.

The shop manual does not refer to a clearance necessary between the disc and the pressure plate.

I think that only the "long throw" slave can solve this now.

The total assembly height of the your new clutch as an assembly is greater than the original.

In all fairness, the original clutch was "finagled" (messed around with) to get it to work.



The Dual Friction I have in my car does give me the clearances that I need.

If I remember correctly though, Hall told me to use a "long throw" slave with it. That is probably what is in the car now.

It is only a 10-1/2" disc which I would prefer to be 11" but life is just compromise after compromise and you need to pick your battles. One can't fight every one. There are just too many to deal with?

The 10-1/2 has a different engagement feel than the 11. It actually feels like it has less travel of the pedal, but it is probably just that it hooks up a little differently.

I feel the difference in my clutch foot.


Hang in there. Remember there are a lot of folks who can hit really hard, some call that fate. The champion, aka, just a survivor these days, is the one that can take the beating while others fail, shrivel up and cease to exist.

quote:

Originally posted by Peter Fenlon:
will not give me half a millimetre between the clutch and flywheel

What are you talking about here Peter?


And the other half a millimeter between Throwout bearing and your "3 fingers" is not enough! You need to take the ZF off and modify your Throwout bearing so it allows more spacing. I dont remember if you told us wether its the type with the various spacer rings? The spacing can ONLY be measured by separating the bellhousing from the ZF and bolt it onto the Engine. I posted some sketches a while ago, perhaps you have them. You CAN NOT rely by feeling on the arm alone if there is space between throwout bearing and your 3 fingers BECAUSE even if you push your throwout bearing full aft the arm can be rocked a little back and forth since the forks that slides the throwout bearing forward has some play. That is the play that can fool you and that is the REASON the measurements MUST be done with the bellhouse OFF the ZF and ONTO the engine.

btw did I mention NO SHORTCUTS?

Secondly the displacement on the MASTER and SLAVE are in direct relation. Displacement = Radius of bore squared and multiplied by π and multiplied by the stroke. I.e. if they have same bore they have same stroke! PROVIDED there is:

a) no damage/internal leak and/or the fluid supply to the master is not starved (can happen i.e. if wrong parts are used when rebuild and piston does not retract/return fully to open for reservoir fluid access to bore)
b) no air trapped somewhere. It can be really tricky to get all the air out. I mention this again because it is very likely.

So if your strokes does not match based on a quick calculation of the displacement there is something wrong like a or b above. It is really not rocket scientism but no room for shortcuts.

I am not reading this out of a book Peter, this is from working with these things and latest when I changed engine last year with different flywheel etc. I went thru the whole procedure again with removing the bellhouse and measuring for sufficient play between throwout bearing and clutch (multi fingers) It is unfortunately an essential and absolutely required procedure. Guess you can put it together with standard OE parts and be LUCKY there is enough space. But there is no guarantee for that.

Please let me know if I am confusing you and if my explanation is not making any sense?

Jan

Hello Goodroc,
in my time working as a service rep, for mobile Crane companies I have been to 50 countries in Europe Africa the mid East and Far east.

The reason I went there was only because I had experience of the product that other engineers in those countries didn't have.

I have to admit that your post doesn't really help, your experiences are OK for you of course but not in my case.

I will NOT remove my ZF for a third time been there and done that.

but thank you for your input.

Peter I dont have a crystal ball. But my estimate is you will end up removing it anyway rather sooner than later. If there is insufficient play between the components it will only get worse when everything gets to operating temp and also as your clutch plate wears the 3 fingers will come towards the throwout bearing and reduce the play until it eventually reduces to zero and the throwout bearing wear will then speed up.

quote:
Originally posted by Peter Fenlon:
will not give me half a millimetre between the clutch and flywheel

what were you talking about there?

And have you considered my other points concerning MASTER and SLAVE cylinder regarding starvation and air etc?

really only trying to help.

I found this (can't believe I didn't remember )

quote:

Originally posted by Peter Fenlon:
posted October 22, 2016 11:12 AM in "Throw out bearing touching clutch"

...info from McCloud...needs 12.7mm of travel from the time the bearing touches the fingers to full release.
You should get about 1.524mm gap between the pressure plate and disc at the time of full release.
..and you have a gap between the bearing face and the fingers of 2.54 to 6.35 when the pedal is in the home position..

so this implies you need (12.7 + 2.54 =)15.3mm at the ToB, this would mean you need (15.3 X 1.4 =) 21mm at the slave.

having the ToB just not touching when the pedal is in the home position would require (12.7 X 1.4 =) 18mm at the slave.

1.524mm is 60 thou and that sounds about right, I have always worked on a minimum 40 thou required.

This is one of those times I wish I was back in the UK, I'd hop in my car and go round and help fix it. I feel somewhat helpless from a such a distance.

Julian

Hello Folks,

I fitted the long throw slave this morning and I now have 1 mm clearance between the TOB and clutch fingers, and 20 thou between the flywheel and clutch disc.

Total travel of the slave cyl is now 15.5mm

I think the word in America is Geronimo!

thanks to all for their input. Peter.

Interesting that it appears McCloud stated the required stroke at the slave versus at the ToB

quote:

the word in American is Geronimo

Congrats, Peter!

Shouldn't you be yelling in Italian!


(Actually, "Geronimo" is what we yell when we start an unbelieveable adventure, like jumping out of a plane.... "Wahoo" is a good one for the extatic conclusion. Wahoo is also the famous mascot for the near-world-champion American Baseball Team, the Cleveland Indians...)

.020" is marginally ok when cold but as it heats up, the clutch will hang enough to grind gears.

Unfortunately you need to find another .015" minimum.

Off hand I would question the disc that you have.

It MUST be a dedicated Pantera disc with minimal Marcel. That is the only place you will find the needed additional clearance.

Peter,

Although you don't want to hear this, I agree with Doug, 20 thou cold isn't enough and there is still something amiss with your clutch system.

Maybe if you mash the pedal to the floor on every shift you'll find gears without grinding, but I'm pretty sure you need to get back in there and it might mean removing the ZF again.

Julian

I'm lucky, as I have not had as much trouble as Peter with either of my clutches (a stock 3 Finger, and a Centeforce diaphragm), but isn't there some amount of "wear" and "settling in" that will occur when a brand new clutch is installed?

Marcels compress, minor high spots are burnished off, and the disk compresses due to the thermal and friction environment?


Just hoping for the best.....

Rocky

quote:

Originally posted by Rocky:
I'm lucky, as I have not had as much trouble as Peter with either of my clutches (a stock 3 Finger, and a Centeforce diaphragm), but isn't there some amount of "wear" and "settling in" that will occur when a brand new clutch is installed?

Marcels compress, minor high spots are burnished off, and the disk compresses due to the thermal and friction environment?


Just hoping for the best.....

Rocky

Just assembling and installing the clutch sets the Marcel.

Will there be a seating of the clutch lining? Sure, but not .015". Maybe .005 at most BUT in the ZF it isn't just the synchros, it's the gear cones, shipping it to Lloyd, waiting and hoping you can pay the bill?

I don't trust anyone on these parts. The guys who are selling them to you think that they are experts and you are just a smuck.

This really smells of the wrong disc in there.

You might be able to measure the clearance of the Marcel on the disc that is in there like you did on the disc PP clearance. Then compare that to a know correct disc.

I don't think that I have a disc out of the car here. A pressure plate, yes, but that doesn't help.

I positively guaranty you that if you talk to the Byers or Dennis at Pantera Performance(which is the best place to buy a clutch from), describe what is happening to them, they are simply going to tell you that you have the wrong clutch in there.

It doesn't matter what "expert" you bought it from. Something is not right with it.

It could be the "Chevy Expert Syndrome" again at play.

Remember. THEY are the expert, WE are just smucks.

There has to be a point where all this grey hair, skinned knuckles and Rolaids consumption registers as significant documentation of experience.

@ Rocky, the actual thickness of the clutch lining on the disc may also be thicker now then on the original disc. Justification for that would be because that is a "premium lining".

I can't think of another car that has the same issues with clearances then the Pantera? Buying a clutch from some of these people is like talking to the kid who works part time in Staples.

I needed a "customs envelope" to ship to Germany. They told me to go to the "Custom Print Shop".

But why are the few FACTS about a Pantera clutch requirements on a top seceret bases?
when I say FACTS, having a "special" Marcel or a changed geometry fingers statements my be TRUETHs, but a measureable parameter is needed.

I don't think this is limited to the Pantera as my google searches for such information produces many hits for other vehiclies where the forums are going thru similair problems.

You Know, not providing measurable values is not unique to car entuistist as I recall the same when I was working

quote:

Originally posted by JFB #05177:
But why are the few FACTS about a Pantera clutch requirements on a top seceret bases?
when I say FACTS, having a "special" Marcel or a changed geometry fingers statements my be TRUETHs, but a measureable parameter is needed.

I don't think this is limited to the Pantera as my google searches for such information produces many hits for other vehiclies where the forums are going thru similair problems.

You Know, not providing measurable values is not unique to car entuistist as I recall the same when I was working

Why indeed?

I think part of the issue is cost. My CF was $800 from Hall at the time.

A clutch that looked right but fit a Mustang was $290.

So many of the clutch parts are mixed and matched.

You could have a different thickness throwout bearing. It could be the thickness of the pressure plate. It could be a difference in the assembly height of the springs in the pressure plate.

I think also that on the engineering side of producing a special clutch just for the Pantera there is a presumption that the car has a "normal" adjustment procedure.

I will also say that there is quite a use of Chevy clutches in Mustangs. I bought an 11" fine spline from Summit for under $200.

It was for use with my Doug Nash, aka, Richmond 5 speed, which at the time had no clutch specifically built for it.

I needed to redrill the flywheel for the different pressure plate mounting pattern.

That transmission used a Chevy fine spline disc with a Ford length and nose.

Fortunately the assembly had no issue with enough assembly height to get the needed clearances.

The Pantera ZF bell is not the case. It really is the culprit here causing these issues. It's too small.

Maybe one of the aftermarket bells would help?

Ask Comp2. He's got one.

to me, the mixing and matching would make it nearly manditory key information be available.

I feel I should just shutup from beating this horse until I am able to make my own measurements in leu of finding bits and pieces on the internet.

But like for Peter's problem, the simple stroke of a stock master cylinder and slave is still undetermined.

quote:

Originally posted by JFB #05177:
to me, the mixing and matching would make it nearly manditory key information be available.

I feel I should just shutup from beating this horse until I am able to make my own measurements in leu of finding bits and pieces on the internet.

But like for Peter's problem, the simple stroke of a stock master cylinder and slave is still undetermined.

I don't see where an open discussion of this is detrimental to anything or anyone.

I think it is helpful to the Pantera community.

Ask Peter if we are screwing him up? Peter?

what I meant for me, is that all I bring to the discussion is a "method" to solve tah is foreign to most, but I don't have any real knowledge that would actually help.

I can feel for Peter and I have expressed my intents in that I hope I have not added confussion and even now, not truly Knowing if it is solved

-30-

Just for information.

I bought my spinner disc from Becky at Pantera performance.
Also bought my pressure plate from them.
I note that I did mention that I was having my old spinner relined.

I think I got the correct parts for they were kindly sent to me by Mike Drew.

Only time will tell if all is well, but I shall keep the forum informed.

In the light of my troubles I would like to see
a well documented description of how to instal
1 a 3 finger clutch sytem or
2 a centreforce clutch system.

If I were doing it it would begin with

Buy ALL your clutch parts from one vendor who also issues a written description of how to fit it and ALL measurements required.

Best Pete,

Discussion only helps I find thanks again chaps

Peter,

Since you purchased your disk and pressure plate from Pantera Performance, perhaps you should speak with Dennis. He's always happy to offer advice. Also, he's familiar with your clutch assy. and has likely seen your problem before.

Here's an interesting description of the Clutch assembly, by Fred Matsumoto (PI News "Window Monitor).

This came from PI News, Vol 16, No. 3 in 1991.

I think it's the first issue Doug received, because he pretty much quoted it in one of his earlier posts in this discussion!

Not trying to stir up trouble - just post up some history.

Rocky

quote:

Originally posted by Rocky:
Here's an interesting description of the Clutch assembly, by Fred Matsumoto (PI News "Window Monitor).

This came from PI News, Vol 16, No. 3 in 1991.

I think it's the first issue Doug received, because he pretty much quoted it in one of his earlier posts in this discussion!

Not trying to stir up trouble - just post up some history.

Rocky

Doug who?

You know, that "Shelby Doug" guy...

I think he is French (maybe Haitian or Jamaican - possibly Canadian?), his middle name is "Marcel".




This one.

Thread on Marcels

quote:

Originally posted by Rocky:
You know, that "Shelby Doug" guy...

I think he is French (maybe Haitian or Jamaican - possibly Canadian?), his middle name is "Marcel".




This one.

Thread on Marcels

You mean this guy? Looks like a disruptor to me? He can't even spell his own name right? What's he know 'bout Pantera clutches? Just a dumb as s.

Anyone any good at working out hyd ratios.

I have been having similar issues to Peter and ordered a new master and slave from Germany. The slave is good at 1.00" bore etc but I notice the master bore is only .7" as opposed to the OEM of .75". It also has a longer stroke at 1.225" as opposed to the OEM master of 1.125".

Adjusting the master pushrod to the recommended 2.91 to 2.95 I am not able to select gears and not getting any clearance at the clutch plate.

I am hoping to be able to exchange the master to the correct .75" but if not what would the master pushrod length need to be to give the required/correct amount of travel/displacement etc.

Cheers

quote:

Originally posted by Horace Cope:
Anyone any good at working out hyd ratios....

the slave has a 1” bore which gives it (pies are square) 0.787 “” area

the master cylinder with 0.70” bore have 0.386”” area
stroking its 1.225” would spurt (area X stroke) 0.473””” volume to the slave
and this should stroke the slave (volume/area) 0.601”

the master cylinder with a 0.75” bore would have 0.443”” area
stroking its 1.125 would spurt 0.498””” volume
and this should stroke the slave (volume/area) 0.633”

the BIG thing is getting the pedal to stroke the MC its entire stroke.

Do you have the peddle effort reduction linkage? Assuming so,

The initial push rod length of 2.93” is to set the initial ANGLE of the link.
IF too shallow, the pedal will lock in the up position
Too steep and even though the pedal is easy to push, the MC stroke will be reduced
Thus ALWAYS measure slave stroke

Thanks

Yes I have the ERK fitted. The travel of the piston in the slave from its stop is 40mm (1.575"). However thats measuring it manually

How can I ensure I am getting full travel on the MC and subsequently the correct amount of stroke on the slave. It states the MC pushrod should be set at 2.91 to 2.95 but thats based on a .75 MC I assume.

quote:

Originally posted by Horace Cope:
How can I ensure I am getting full travel on the MC and subsequently the correct amount of stroke on the slave.

Measuring the slave will let you know if you are getting the full stroke of the MC. use the calculated strokes based on volume transfer. One can assume there could be "some" loss, maybe due to the swelling of the hose with pressure.

quote:

It states the MC pushrod should be set at 2.91 to 2.95 but thats based on a .75 MC I assume.

Using basic lever/link/hydrualics understanding, the push rod lenght is NOT dependant of the MC bore. But the relative position of the piston in the cylinder and its mounting to the pedal box. So if the mounting is the same, the 2.9 would be the same. However, IMO, the 2.9" is only a referance value, BUT the initial angle of the toggle link is CRITICAL.

one of the real world influences i have not considered is the pedal travel and what limits it

That ONLY matters IF you are not getting enough clutch disengagement. You determine that with a feeler gauge.

Mike,

As JFB states the length of the rod is to set the relative position of the effort reduction linkage, so should be master cylinder independent. The caveat top that statement is that the master cylinder piston is in the same relative position, which may not be the case as the stop ring may be in a different location and/or the cup that the rod sits in can be deeper on different master cylinders.

To be sure you should measure the distance from the center of the piston cup to the mating flange (back side of bolt flange) and compare on the two cylinders.

You should also do same with the slave to ensure the required rod length on the old and new slave is the same.

Julian

to adjust the push rod to set the initial angle of the ERK. I would THINK setting the center pen a given amount out of line with the end pins would be the most accurate.

HOWEVER, I do NOT know that value and my illustration is NOT to scale