Is this common problem?

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adriver

Blazing Apostle
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What I'm running into is this.
Experts please.
Stock B body.
New rebuild parts from Brewer's
Original Z bar, peddle rod and fingered pressure plate.

First time I've monkeyed with a MOPAR 4 speed though.
Everything works fine.
Concerned about the throw out bearing clearance.

If I have enough clearance between the fingers of the pressure plate and the throw out bearing that I'm comfortable with, the peddle doesn't quite make it up all the way on a slow, normal release.
Tap it with your toe and it pops on up the last something like 1/2 inch.
(Which is actually just about that much past the brake peddle, They are not exactly even at rest.)


If I take the little spring off between the Z bar and the clutch fork to check and get what seem to be a good factory 5/32 play at the end of the clutch fork.
Then peddle pops up good on a slow release but there sure doesn't seem to be a lot of space between the bearing and fingers.
How close is it supposed to be to the fingers and how can you tell with the bearing that far up out of sight?
I can hear it "click" when moving the clutch fork checking. But forget actually measuring it.
I'm trying to say I THINK there is SOME clearance when adjusted "properly" but no room for clutch disk wear, I'd say.

Do I need to live with the toe tap? I'd rather do that than risk a new throw out bearing.

Pulled this from another thread.
Maybe a "peddle rod" (wear) problem.
Order a new one and then what?
No difference I'm afraid.


scan-small-jpg.jpg
 
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Mine did that as well. I have 1/8"-3/16" gap between the bearing surface and the PP fingers. If I remember correctly, mine came out of it after a while. I lubed all the points with white lithium and rechecked after a week of driving.
 
I've had this too.
I changed the Z-Bar bushings.
There are nylon bushings on the frame side and the engine side of the Z-Bar.
 
They aren't the bushings in the pictures.
They are inside the tube section of the Z-Bar.
 
I've had this too.
I changed the Z-Bar bushings.
There are nylon bushings on the frame side and the engine side of the Z-Bar.

New bushings ("bearings") and other small parts already from Brewers.
New fork rod. Notice the picture does't show a "jam" nut on it.
I've got one on mine to prevent the "adjusting nut" from turning out of position.
Was that my idea or did it come with one?
Probably my idea.
 
Do you have the return spring on the fork?
Ted

I'm not sure which one you are asking about from the picture.
If it's the onethat goes from the clutch fork to the Z bar, then yes.
A new one.
That's what I'm taking off to try and get the 5/32 movement when adjusting it.
Have to eye ball that measurement.
Looking at the picture, it's sort of confusing.
And I'm not sure about this.
I'm thinking that is a six cylinder application maybe.
I'm working on a B body and the picture shows two different "fork return" springs.
I don't have one that goes from the fork to the "release fork" to the "clutch housing".

Does anyone else's clutch peddle come to rest just slightly past the brake peddle?
I'm wondering if this is just an "imperfect system".
 
New bushings ("bearings") and other small parts already from Brewers.
New fork rod. Notice the picture does't show a "jam" nut on it.
I've got one on mine to prevent the "adjusting nut" from turning out of position.
Was that my idea or did it come with one?
Probably my idea.
......................

Jam nut = Good idea.
I thought there was a nut on both sides of the clutch fork. I'm gonna have to take a look now.
 
Do you still have the over-center spring on the pedal?
If so you need to remove it with a diaphragm pressure plate.
If you have a borg and beck pressure plate w/3 fingers it should have the over-center spring on the pedal, but you might want to try removing it to see if the pedal returns better.
 
Does anyone else's clutch peddle come to rest just slightly past the brake peddle?
this part is normal
As already asked; is the factory anti-rattle spring, also called fork-return, in place ?
Is your downrod from the pedal assembly rubbing on the edge of the big oval hole in the firewall?

Remove the downrod from the Z-bar. Now gently push the pedal down about 2 inches and then let it back up to the stopper. Does it still stick? Then fix the pedal assembly. If you side step the clutch at 1 to 2 inches travel, that pedal, with the overcenter spring installed should slam into the stopper with some pretty wicked force.
But if it works smooth as butter now, then the pedal assembly is Ok, move on to the Z-bar. That bar, with both the downrod and the forkrod removed, should move smooth as silk on the unlubed nylon bushings. The bar should be about parallel to the road and about at 90* to the centerline of the car AND the outboard end should be captured by a clip so that the assembly cannot move laterally. The frame bracket must be welded to the apron in such a manner that the Bar can only rotate on the bushings and move in no other direction.
Finally, the TO bearing has to be sliding back and forth with just a tiny amount of force. If you assembled it with common thick gun-grease then you will have to wipe thatchit out of there as best as you can.
I assume the following;
that the disc and pressure plate are a matched set from a reputable source, and that you installed the disc with the side marked "flywheel side", next to the flywheel, and that you did not bend it by hanging the trans on it during the install.
And that your Z-bar is correct for the application, and that the TO fork is the correct length for the bellhouse.
Ok, now with all the players properly functioning, it's time to re-install the rods,secured by the proper retaining clips, and to make sure nothing rubs on stuff it's not supposed to rub on.
If it still hangs up; no this is not normal, but IDK what's causing it.
unless maybe, you wrongly installed the parts on the fork rod and it is somehow hanging up. Look in the picture; there are not two nuts on that rod for a reason. There is just one jam nut. You might be able to fit two on the engine side and jam them together, but do not put one on each side of the insulator/swivel ....... unless you space it away from the insulator with a thin-walled tube-spacer. This works really slick with my TTIs. But I installed a common nut on the engine side so I can adjust it with hot headers. And after I lost the nut off the end, I drilled the rod and installed a hairpin in the hole. And after I lost the hairpin, I installed a common cotterpin. lol. It's all good now.
TIPS
This stuff all gets pretty hot with headers sitting right there. You gotta make sure nothing actually runs against the header especially the forkrod, cuz the nut wont stay tight, that's why there is a jamnut on it.
If anything moves in any way it's not supposed to, then your adjustment will change.
There is a difference between a 340/383 pedal assembly and a regular assembly. The pedal ratio is greater on the 340/383 set to compensate for the different clutchs.
6cylinder Z-bars are different from V8s
That's all I can remember

Happy HotRodding
 
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I'm following up.
I can't prove it but I think the eye holes on ends have to be just right.
There must be some cam action inherent to the shape.
Before I put this car together I welded up an end because it was worn.
I used my best guess on the shape.
I tried ever thing.
Greased new boot.
Checked for binding.
Adjusted this way and that and it only seemed to work correctly with VERY little clearance between the clutch fingers and throw out bearing.
So I gave up and ordered a new rod.
When I got a new rod from Brewer's the problem disappeared.
I'm happy with the throw out clearance and it doesn't tend to hang.
20190817_103121 (Large).jpg
20190817_154056 (Large).jpg
 
I had the same problem with my 69 dart when I put it together. I welded up the ends on the rod from the clutch to the z bar, I also built up the areas on the z bar where the rods press on. That totally fixed my problem.
 
Just remember guys, every little bit of slop in the linkage and the throw out bearing gap get's you the free play that prevents the clutch from slipping. The springs in the pressure plate provide the clamping force. The slack keeps the pressure plate and disc engaged.
 
Oddly enough, the buttons on the Z bar that the eyelets attach to are fine.
No apparent wear.
That is the original rod to the car.
The only thing I did was weld up the eye as you can see in the picture.
The distance between holes on the new rod seems to be the same length as the old rod.
But as I was pondering what might fix the issue a longer rod did cross my mind.
 
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