PEDAL TO Z BAR ROD

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WAYNE0

WAYNE0

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The rod that goes from the clutch pedal to the z bar has an oblong hole at each end. The end where it goes on to the clutch pedal seams to have more slack than normal. Not sure how to explain it. When i push the pedal in it moves a little before it pushes the rod. The pedal has a round stud and the hole in the rod is oblong. I have notice some play there. The clip that holds the rod on is tight. I dont notice any play where it attaches to the z bar. Could the hole in the rod at that end be warn out ?
 
This is how they are made, factory. Be sure to have the correct clip and washer behind it.
 
My answer would be ‘yes’ . It could have excessive wear. When I got my car I was surprised how much wear there was visually. They are not too hard to remove to take a look at. But as said above the holes are somewhat oblong even when new.
Yote
 
There is some play . I put a spring from fork to bell housing.

z-bar 008.jpg
 
That spring shown in post # 5 is similar/same location on stock bellhousing, and should take out slack up to pedal, and keep release bearing from riding on pressure plate ..
Oblong holes in rods normal, to a degree, lol
 
When I got my dart it's rod had so much play that my clutch pedal would not return all the way. I welded it to fill in the wear spot. Now my pedal returns to where it should and shifts great. So I would say yes they do get loose with excess wear.
 
My 72 Duster 4 speed had lots of play in it on the rod from the pedal to the Z bracket. The round holes were oval from 50 years of wear. I took it out & had it welded closed on both ends then used a die grinder to open up the holes again so they just slipped over the stops on the Z bracket & pedal rod. I gained 1/2" & my pedal came back up to the brake pedal. There is slight play in it if it slides over the stops. I believe that is how it was when stock.
 
Daves69 said:
You might check this...............................
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Click to expand...
I have seen that from National Moparts up here in Canada. I maintain as long as the hole is large enough to go over the end stop it has play. The part did not start out oval. If you ever drove a car with so much play in the clutch linkage you would repair as much as you could. There is only so many places to tighten the linkage. The individuals that installed the headers before I bought it really pushed the clutch linkage around. Before I did this & cut the bump in front of the Z bracket on the clutch fork side the pedal only came up 3/4 the way it should have. It now comes all the way up. I am happy with it.
 
I can't argue success. Great that it works for you.

FWIW, I've had my Barracuda since '80. I helped the previous owner with it for several years before I acquired it. The pedal rod has always had oblong holes and I've never had pedal return issues with a B&B PP.

1676861155736.png


1676861515798.png
 
Daves69 said:
I can't argue success. Great that it works for you.

FWIW, I've had my Barracuda since '80. I helped the previous owner with it for several years before I acquired it. The pedal rod has always had oblong holes and I've never had pedal return issues with a B&B PP.

View attachment 1716052700

View attachment 1716052703
Click to expand...
I guess my Duster has a lot more miles on it thanks. The car was a rotisserie car, body like new but linkages & wiring original.
 
Sorry- don’t mean to wake a sleeping dog.

My 72 Demon all the sudden started to not return the clutch pedal all the way. If I tap the pedal it clicks (spring sound in back ground) and it snaps back into normal spot.
I crawled under the dash and saw my rod at the pedal side (goes down to the z bar) is got a lot of play - never before… sitting for last 2 years. So this is néw.
Brewers I guess is only solution or take off and weld up and try to grind. Going to take apart this weekend. I mean it’s 50+ years old…. Warranty? Lol.
 
Well heck than. Maybe the bushings are shot. Looked at Brewer’s and saw HD and Std. Need to measure pivot shaft to see what I got. 340/4 I figured HD but maybe not. Thanks.
 
The minimum distance between the oblong holes in the peddle rod should be enough to return the pedal to just "over center" for a B&B style clutch when adjusted correctly. That is where the "over center" spring takes over and lifts the pedal to the up stop.
Check for loss motion in the torque shaft through the fork, a deteriorated / collapsing washer on the clutch adjust rod, or possible loose / bent fork pivot. Also watch the pedal pivot area for worn bushing. Watch it while a helper works the pedal up and down.
 
Daves69 said:
The minimum distance between the oblong holes in the peddle rod should be enough to return the pedal to just "over center" for a B&B style clutch when adjusted correctly. That is where the "over center" spring takes over and lifts the pedal to the up stop.
Check for loss motion in the torque shaft through the fork, a deteriorated / collapsing washer on the clutch adjust rod, or possible loose / bent fork pivot. Also watch the pedal pivot area for worn bushing. Watch it while a helper works the pedal up and down.
Click to expand...
the only thing i see is where the clutch rod goes onto the Z bar and pedal it has a lot of play.
 
Everything you need to know, has already been said in this thread.
Except;
1) there is a rubber bumper at the top of the pedal travel, to park the pedal in the exact right place, for everything to work correctly, almost no matter how worn the factory oval slots get to be..... when everything is correctly assembled, with no missing parts,
and the free-play is properly adjusted .
2) if your clutch is NOT factory, but is a HD 3-finger type, then you need the V8 pedal-box AND the HD 340-UP, overcenter spring.
3) Also, the TO fork needs to rest at the front of the window in the BH.
4) And the Z-bar needs to be parallel to the road in front view, and at 90* to the centerline of the car, in plan-view.
5) And the down rod has to be laterally centered in the oval firewall window, and not rub on any edge during it's normal travel.
6) the E-clip needs to be installed on the pivot-pin (which needs periodic service) of the pedal to keep it from rubbing on stuff and hesitating to return to the parked position.
7) and finally, the adjuster rod from the Z-bar to the TO fork, at rest, should be approximately parallel to the road in side view, and, in plan-view, approximately parallel to the centerline of the car.
8) don't forget the so-called anti-rattle spring, which performs it's function by pulling all the slack out of the system right from the fork all the way to the pedal; and now you can actually measure the true TO fork-retraction off the fingers which equates to measuring the freeplay. BTW, the factory recommended freeplay is generous enough so that you may not have to readjust it for many thousands of miles. But, the only freeplay that you cannot run is ZERO. So you can run as little as you like, until you get tired of adjusting it too frequently...... which, with headers, is a very real thing. On my linkage I modified the system and now I can even adjust it with hot headers, and it only takes a minute or two...... so guess how much freeplay I run, lol.
Happy HotRodding
 
Here’s another alternative: Peffley Performance Chassis & Parts

I bought a nicely designed adjustment screw and the lever in question here from him at the Indy swap meet. He added Heim joints to make it much better and more adjustable. I tried to add a picture, but my internet is miserable here today.
 
AJ/FormS said:
Everything you need to know, has already been said in this thread.
Except;
1) there is a rubber bumper at the top of the pedal travel, to park the pedal in the exact right place, for everything to work correctly, almost no matter how worn the factory oval slots get to be..... when everything is correctly assembled, with no missing parts,
and the free-play is properly adjusted .
2) if your clutch is NOT factory, but is a HD 3-finger type, then you need the V8 pedal-box AND the HD 340-UP, overcenter spring.
3) Also, the TO fork needs to rest at the front of the window in the BH.
4) And the Z-bar needs to be parallel to the road in front view, and at 90* to the centerline of the car, in plan-view.
5) And the down rod has to be laterally centered in the oval firewall window, and not rub on any edge during it's normal travel.
6) the E-clip needs to be installed on the pivot-pin (which needs periodic service) of the pedal to keep it from rubbing on stuff and hesitating to return to the parked position.
7) and finally, the adjuster rod from the Z-bar to the TO fork, at rest, should be approximately parallel to the road in side view, and, in plan-view, approximately parallel to the centerline of the car.
8) don't forget the so-called anti-rattle spring, which performs it's function by pulling all the slack out of the system right from the fork all the way to the pedal; and now you can actually measure the true TO fork-retraction off the fingers which equates to measuring the freeplay. BTW, the factory recommended freeplay is generous enough so that you may not have to readjust it for many thousands of miles. But, the only freeplay that you cannot run is ZERO. So you can run as little as you like, until you get tired of adjusting it too frequently...... which, with headers, is a very real thing. On my linkage I modified the system and now I can even adjust it with hot headers, and it only takes a minute or two...... so guess how much freeplay I run, lol.
Happy HotRodding
Click to expand...
The only thing im not to sure is what for A body the pedal assembly came out of. Im going to reach out to the guy i bought it from and find out
 
For 10.5/10.95 scalloped clutches;
1) If you are running a 3-finger clutch;
If when the freeplay is set to ~1inch, AND the pedal can be extended to NOT less that 1" from the floor, AND if this gets you adequate clutch departure of .080 or more, then you have the right pedal box.
Or;
2) If you are running a HD version 3-finger clutch, (like what came in 340/383 cars) then you will need the HD 340/383 pedal-box, which has
a) the long-ratio pedal, to increase departure, and
b) it has a bigger heavier overcenter spring to deal with the extra pedal-effort, and
c) it has the bracket covering the overcenter spring,to help the pedal-box deal with the HD spring.
But;
3) If you are running a diaphragm clutch, then;
a) the HD overcenter spring will have to be removed, to prevent the clutch from sticking to the floor at high-rpm, and
b) with the spring gone, the bracket is no longer needed, and
c) the diaphragm will work with the 6-cylinder short-ratio pedal, albeit with a lil more pedal travel, which then
d) makes which pedal-box you have, a non-issue
I think that's right.
4) no matter what you run, the TO fork has to park near the front of the window in the BH, AND the adjuster rod that goes from there to the Z-bar has to end up about parallel to the road in side-view, and about parallel to the centerline of the car in plan-view. If it is not, then you will have issues in both effort and departure.
Not having it set this way, has troubled more than a few hot-rodders, because of the several possible combinations of various parts;
I know, for 67 up A-bodies, there are at least;
2 pedal boxs, with 2 possibly 3 springs, and with or without the bracket
3 aluminum SBM bellhousings,
2 Z-bars,
3 inner Z-bar pivots,
2 or 3 forks,
3 fork pivots
2 adjuster rods and
2 TO bearing assemblies.
By the math, this comes to about 2600 ways to screw up.

In my car I have a 10.5 CenterForce diaphragm, and it runs the 340 pedal-box, with no overcenter spring and no bracket. I get adequate departure with the pedal extended to slightly more than half-way, at the very modest freeplay adjustment I use.
At some point in time, I added a junk-box overcenter spring, that IDK what it came out of, to help pull the pedal back up to the dash-stopper. Yes, I do, have TTI headers, and yes I did run into interference. The Z-bar needed a lil offset, and the headers had to be "clearanced", cuz I was not messing with the perfect-functioning clutch. AND,
I re-engineered the adjuster rod, for ease of adjustment access ..... which is a fancy way of saying, that I got rid of the interference loc-nut and got rid of the subsequently required double-nut locking system. Instead, I put one nut on the radiator side of the metal swivel, then a tube spacer and a second nut on the back-end. The spacer pushes the back-end nut out to the back for ease of access, cuz the header is right there. On the very end, I drilled a hole to receive a hairpin, cuz one time that back-end nut came loose and disappeared, along with the spacer. This allowed the freeplay to change. Eventually the hairpin disappeared so I installed a soft cotterpin. With the system now working properly, I use a socket and extension to loosen the Back-nut, spin the Front-nut down a turn or two, and lock it back up. and yes this can be done with hot-headers. Because this only takes a few minutes, I run a very small freeplay; just enough to keep the TO bearing off the Diaphragm for the summer.
 
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Im running the diaphragm type clutch I took the overcenter spring out. The bracket your talking about taking out is it where the overcenter spring hooks on to ?
 
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