[DeTomaso] Clutch Master Cylinder and Shackle

Daniel C Jones daniel.c.jones2 at gmail.com
Thu Jun 12 15:24:00 EDT 2008


> I would have to believe that if a guy Dan's size can do this without a
> hole any one can!

It's back together and no hole was needed.

> The answer is yes you can just pull the pushrod through the boot to
> remove.

Ugh, now you tell me.  I pulled the pushrod out of the OEM master and
it required a snap ring removal so I figured the CNC would be the same.

> The CNC masters do come with a pushrod and the vendor should have asked
> if you have a late car or not because the length as you said is
> different; although if memory serves it's the later cars that use the
> shorter pushrod. It's also not uncommon for people to just re-use the
> existing pushrod to avoid having to get the clevis pin out of the pedal
> assembly.

This was installed by a previous owner or his mechanic.  In a box of parts
provided by the previous owner, I found the long pushrod which is too long.
The short pushrod is in the CNC master.  The previous owner purchased the
parts from PPC so I called them.  The lady on the phone said Dennis couldn't
be disturbed but she measured the two pushrods they provide.  The long one
was the same length as mine.  If she measured the short one properly at 2",
it is shorter than the OEM pushrod (which I measured at 2.36" or 600mm).

> Three things interfere: first, most Panteras use a tiny circlip on the pin
> end(s) that either breaks or goes flying never to be seen again when you
> try to remove it from the pivot pin in the shackle.

This pin was drilled for cotter pins, not circlips.

> Third, the pin, once the circlip is out, is often rusted in place or has a
> worn spot that acts as a detent to prevent the pin from being pushed out-
> and there simply isn't enough room without a hole-saw to reach the pin to
> knock it out.  If you're past all this, no hole saw will be needed. This time.

This car has less than 17K miles so the pin and clevis were not worn.
Probably should lube the linkage while I'm thinkimg of it, though.

> The actual length adjustment on the shaft is outlined in the TSBs, of which
> all Pantera owners should have a copy.

I've got the TSB's.  It looks like the distance from the clevis hole centerline
to the mounting face of the slave body should be 2.95".  I'd rather not pull it
all back apart to check this but maybe I can get someone at PPC to check the
same dimensions on the CNC master they sell.

> The thing is, there is almost *never* a need to remove the pin and the clevis
> at all!  The smart way to change a master cylinder is to just unthread the rod
> from the clevis, leaving it (and the troublesome pin/circlips) in place.

That wouldn't work in this case.  I wasn't swapping out the master and I had to
remove the clevis so I could run a tap through it.  The last thread was damaged.
It takes a 8mm x 1.25 tap, BTW.

> Having said that, it sounds like Dan got hosed by somebody installing a new master
> with the wrong pushrod, or the wrong pushrod/clevis combo.  So if he can't get a
> longer pushrod, he'll need a longer clevis (I've seen them in two sizes too).

It's got the short pushrod that came with the CNC master which I think is too
short and the long one is too long.  I should have pulled the short one out
and compared it to the OEM.  If nothing else, I can measure the freeplay I have
now to figure out how much longer the pushrod needs to be.  The clevis is also
the short original one.  A longer one might just put the pedal where I want it.
I need to bleed it and make sure the adjustment back at the transaxle is okay
before I resort to a custom pushrod.

Does anyone know if the CNC bore is the same size as the OEM?

Thanks for all the help guys.  It's much appreciated.

Dan Jones



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