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Clutch adjustment advice (for a hack)

Bleep Bleep

Bleep Bleep

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Bought the 66 HP2 sight unseen and have zero knowledge of history unfortunately. The clutch engages at very top of travel, is super stiff (entire bottle of Viagra stiff…as I’ve heard anyway), and feels like less than 1” max of free play.

I don’t know if there’s been any clutch work. Or is the thing is simply worn out?

I’m anticipating pedal stiffness and engage point combo is not ideal for driving fun factor. I prefer a clutch engaging a few inches off bottom, if that may be possible given the circumstances outlined?

Could this be something straightforward enough for a hack, or better to let an experienced mechanic sort out? Thoughts? Thanks.
 
I would lube all the linkage pivots and remove the inspection cover. Adjust the air gap between the throw out bearing and the pressure plate fingers to about 3/16", cycle the clutch a few times and recheck.
 
My 66 has a hitch (over center reaction) about an inch from the upper pedal stop. If I adjust for more free play at top, the pedal stops returning on that hitch point and doesn’t pop all the way up. I can stick my toe under the pedal and give it a slight nudge over the hitch point and it pops up against the bumper. I’m afraid that adjusting the free play just below that hitch point will leave the TO bearing in light contact with the clutch fingers (I have a diaphragm clutch). So I adjust it to where the free play kicks in just a hair above that hitch point and the pedal returns all the way to the bumper. Yours may be adjusted high for the same reason.

I’m heard different reasons for why this is from a worn pin to the large return spring under the dash. I don’t know exactly why it happens.

I can’t tell the make of my clutch. It’s a light gray in color which makes me think Lux or something similar. But it’s not heavy to me unless comparing it to a modern car with a hydraulic set up or multiple plate clutch. But I grew up with Musclecar clutches so a bit of clutch effort is acceptable and normal to me. Typically, a modern diaphragm clutch is going to be lighter than a 3-finger B&B clutch.
 
AR67GTX said:
My 66 has a hitch (over center reaction) about an inch from the upper pedal stop. If I adjust for more free play at top, the pedal stops returning on that hitch point and doesn’t pop all the way up. I can stick my toe under the pedal and give it a slight nudge over the hitch point and it pops up against the bumper. I’m afraid that adjusting the free play just below that hitch point will leave the TO bearing in light contact with the clutch fingers (I have a diaphragm clutch). So I adjust it to where the free play kicks in just a hair above that hitch point and the pedal returns all the way to the bumper. Yours may be adjusted high for the same reason.

I’m heard different reasons for why this is from a worn pin to the large return spring under the dash. I don’t know exactly why it happens.

I can’t tell the make of my clutch. It’s a light gray in color which makes me think Lux or something similar. But it’s not heavy to me unless comparing it to a modern car with a hydraulic set up or multiple plate clutch. But I grew up with Musclecar clutches so a bit of clutch effort is acceptable and normal to me. Typically, a modern diaphragm clutch is going to be lighter than a 3-finger B&B clutch.
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The only comparison I have actually is an 833 in a 69 road runner. Engagement point was perfect, but man I don’t recall the pedal having the action this one does.
Interestingly it sounds like it had the same ‘hitch’ you mentioned. When it happened (maybe less than half) just like said just a light bump underneath returned to the top - maybe an inch travel.
 
Did I read correctly that a new clutch could also have the symptom of a high engagement point? - in addition to the opposite of worn plates.

In trying to learn about what I’ve got, I’m hoping to discover any work that may have been done. Probably wishful thinking in this case.
 
Pedal all the way up, adjust the forks threaded push rod until you only have about 3/16" of play between rods nut/washers and the fork "socket", when pulling the fork back.
 
So... you should be able to pull back on the fork, via the washer, so that the throw out bearing hits the pressure plate and have about 3/16" of slop between the washer and the nut. Adjust the nut until you have that "free play".

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Stiffness is controlled by the pressure plate strength and whether the over center spring is still in the pedal assembly.

If it's a diaphragm pressure plate, the over center spring would / should be removed. OE style Borg and Beck three finger pressure plate, spring should be present.

My HP2 is probably twice as hard to push the clutch in on compared to my 383 Bee, that has a Hayes B&B strip/strip plate in it. I forget what is in the Satellite, if I get to the shop I'll look in it's binder.
 
dadsbee said:
My HP2 is probably twice as hard to push the clutch in on compared to my 383 Bee,
Click to expand...
Yeah. I’d say that’s close to what I have actually. Without enough experience to know better maybe the stiffness in mine is right where it’s supposed to be.
But I do need where it engages to be much closer to the bottom.

Is that related to the free play adjustment you referenced?
 
Bleep Bleep said:
My comparison is to a 383 road runner
Click to expand...
and as I noted above, my 383 Bee clutch is a fairly light pedal to push in comparison to the Hemi Sat and the Bee even has a strip/strip clutch plate in it. Lots more torque in that Hemi to lock up, thus a stronger pressure plate to do so.
 
I’ve heard it said a number of times that the under dash spring should be removed if using a diaphragm clutch, but I’m not sure what this accomplishes unless it removes the hitch or over-center point near the top of pedal travel? I don’t really need a lighter pedal if that’s the only purpose.

I can barely glimpse that spring up at the top of the pedal box. Doesn’t look easy to get to and I’ve heard horror stories of C1 Vette owners trying to remove it on their cars for a diaphragm clutch. They call it the gorilla spring.
 
The reason to remove it with a diaphragm clutch, is that there is very little return pressure when the pedal is all the way down. It can get stuck on the floor and that’s not good.
 
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