[Tony Goat]

So here's the deal guys. I've got a 69 GTO with a M-21. Somewhere along the way the swivel bracket was either broke or cut and re-welded and an angle. This angle resulted in the clutch adjustment rod needing to be shortened as far as possible. With the rod as short as possible this put the clutch petal incredibly high in the car. I was bumping my knee on the steering wheel it was so high (4 inch above the break petal). Not cool.

So, I picked up a new swivel bracket and along with proper rod adjustment brought the clutch petal down inline with the break petal. Here's the issue. The clutch petal can still move up higher in the car and when it does (say I kick it on accident) the end of the adjustment rod, that is seated in the pocket of the clutch fork, will unseat and drop out of its pocket.

What am I missing that is suppose to keep that from happening?

I've looked in the FSM linkage diagram and found nothing to keep the rod from dropping down. Any help would be great.

Thanks,

Tony

[gto4evr]

a few issues here. First off, the clutch pedal SHOULD be higher than the brake pedal. Upward travel should be stopped by a rubber bumper on the pedal brackets so first off make sure the bumper is in place. On the other side of the firewall, there should be a spring pulling the Z bar back towards the firewall and a second spring pulling the clutch fork against the Zbar keeping the rod in between under tension from falling out as you describe.

[webfoot]

There is a small diameter spring which connects the z-bar to the clutch fork, do you have this?

[Tony Goat]

That diagram helped quite a bit. Much clearer than whats in the FSM. I do indeed have the bumper in place for the clutch petal. When its resting up against the bumper, the petal is way higher than any classic car I've ever seen. Not saying its not normal, but it seems off to me.

Anybody have a picture of their petal height in their car for reference?

The only spring that I took off was connecting the z-bar to the frame. Likely the previous owner had this in the wrong location. The spring looks like a double spring, one smaller diameter inside of a larger diameter spring. I'm guessing that those are suppose to be the two springs that serve the two functions previously mentioned?



Thanks for clearing that up fellas.

Tony

[69Customs]

Most cars of that era had clutch pedals that were approx. 1 inch higher than the brake pedal. This was so you wouldn't accidentally hit the clutch pedal while trying to stop the car.

[Tony Goat]

Alright, so the FSM beat me this time. I found the correct diagram for the clutch linkage a page before the firebird one that I was mistakenly looking at. It looked remarkably similar to the one posted here. I now have both springs hooked up in the correct location per said diagram.

Now that I have everything set up and adjusted properly.......my pedal is still higher that what I consider normal. The spring that is attached to the z-bar and the frame bracket pulls the clutch fork off of the throw out bearing and the pedal up against the bump stop. Real light pressure (enough to overcome the spring) will bring the pedal to the "1 inch above the brake pedal" position before engaging the diaphragm spring on the clutch.

The question still remains....

Why is the bump stop so damn high?
Was this to keep the clutch pedal out of the way when not shifting?
Was this normal, and I'm just use to modern cars?

Thanks again for the old man insight, I don't have the luxury of knowing these cars as new cars. I didn't start driving until 96 and my 2nd gen Camaro was an auto.

[webfoot]

I just went out and looked at the pedals on my 68 and the clutch is just a little higher than the brake pedal when resting against the stop. (on my 71 chev pickup, completely different story!)

Can you post pics?

[Tony Goat]

Here are the best angles that I could get showing the pedal height and bump stop. What do you think?

Oh, and excuse the wiring. My dash is due back from Just Dashes in a couple weeks.

[gto4evr]

looks about right to me. Only possibility I can see if it's up too high is that the bracket is bent from standing on the clutch and something's wrong underneath that made the bracket connecting the pedal to the rod bend down opening up the space between it and the stop so the pedal could come up more. My car's still in storage right now but I know I have an extra set of 4spd pedals in the shed. I'll dig them out this weekend and take some actual measurements for you to compare to if someone else doesn't chime in first.

[Dens71TA]

That pedal height looks about right to me too. If you have power brakes the brake pedal is much lower than the clutch pedal. With manual brakes they are about even.

[gto4evr]

Originally Posted by Dens71TA

That pedal height looks about right to me too. If you have power brakes the brake pedal is much lower than the clutch pedal. With manual brakes they are about even.

Damm. that's a great point I forgot all about! the pic of my car shows that as I've got power brakes on it.

[3goats]

Tony Goat
Did you change your power brake booster in the past?
I've ran across a problem with a rebuilt booster that had a shorter rod than my removed original. When installed the brake pedal sat way lower. Had to pull booster and return to supplier. They argued that they are all the same but I found out there not.
I still don't have an answer why it was a much shorter rod (different model,chevelle,wrong year,etc?),but I kept reordering replacements till the right length came in. Pedals looked like yours.
Just thought i'd add my .02