Clutch adjustment?
Thread Starter
Racer
Joined: Oct 2001
Posts: 385
Likes: 3
From: Lincoln CA
Clutch adjustment?
I searched a few different times and did not come up with anything...
So, what is the proper way to adjust the Z-bar clutch setup?
Does anyone have pictures of how the linkage and hardware is installed? And where their clutch return spring is?
So, what is the proper way to adjust the Z-bar clutch setup?
Does anyone have pictures of how the linkage and hardware is installed? And where their clutch return spring is?
Intermediate
Joined: Jun 2005
Posts: 34
Likes: 0
From: Dhahran
Originally Posted by big_G
Adjust the 3/8th in. nuts on the pedal push-rod (under the brake master cylinder area) until you have about 1 inch free-play at the pedal. Jam them so they don't loosen up. 
Also make sure that the other end of the Z-bar is in the 6 o’clock position to assure proper leverage.
Here is a thread that might help.
By the way, I just finished a hydraulic clutch installation. It’s easy, inexpensive (under $150), and it’s smoother than the Z-bar setup i had.
Here is a great thread covering the hydraulic clutch installation.
Good luck.
Thread Starter
Racer
Joined: Oct 2001
Posts: 385
Likes: 3
From: Lincoln CA
Ok, got the engine to fire up so now I'm itching to take it for a test drive.
I have the clutch rod (from the firewall) adjusted all the way down and have good pedal throw, but the clutch is not releasing.
If I put the trans in gear and push a tire (car is in the air and in Neutral the tires spin) the tire wont spin. Then when I push on the clutch pedal I still cannot spin the tire.
My Z bar (engine side) is at the 6'o'clock position...
I measured the distance from my pressure plate spring faces to the outside of the bellhousing and that distance was less then the length of the throwout bearing... Unless the TOB got caught up on something on the trans (we did have to suck that trans to the bellhousing about 1/2" with the bolts, but barely past finger tight...)
So, what could be the issue?
I have the clutch rod (from the firewall) adjusted all the way down and have good pedal throw, but the clutch is not releasing.
If I put the trans in gear and push a tire (car is in the air and in Neutral the tires spin) the tire wont spin. Then when I push on the clutch pedal I still cannot spin the tire.
My Z bar (engine side) is at the 6'o'clock position...
I measured the distance from my pressure plate spring faces to the outside of the bellhousing and that distance was less then the length of the throwout bearing... Unless the TOB got caught up on something on the trans (we did have to suck that trans to the bellhousing about 1/2" with the bolts, but barely past finger tight...)
So, what could be the issue?
Thread Starter
Racer
Joined: Oct 2001
Posts: 385
Likes: 3
From: Lincoln CA
Ok, so I finally got the clutch to release... The jam nut is literally on the LAST thread of the clutch pedal rod.
So it seems I might need to order that tube/heim joint setup to get more adjustment...
Time to go for a test drive now, and see if I really am getting full clutch release.
I am testing it with the car in the air and turning the rear wheels by hand. In gear, clutch pedal in it now turns, although not as easily as it does in Neutral. But that might be because of turning gears inside the trans and the lack of any lube in there.
The trans was "freshly" rebuilt back in '99ish and has maybe 500 miles on it. I drained it and it looked like fingernail polish with all the metal flake in it...
So I'm going to put more "cheap stuff" in and drain it again, and then some Redline 75-90NS.
So it seems I might need to order that tube/heim joint setup to get more adjustment...
Time to go for a test drive now, and see if I really am getting full clutch release.
I am testing it with the car in the air and turning the rear wheels by hand. In gear, clutch pedal in it now turns, although not as easily as it does in Neutral. But that might be because of turning gears inside the trans and the lack of any lube in there.
The trans was "freshly" rebuilt back in '99ish and has maybe 500 miles on it. I drained it and it looked like fingernail polish with all the metal flake in it...
So I'm going to put more "cheap stuff" in and drain it again, and then some Redline 75-90NS.
Melting Slicks
Joined: Apr 1999
Posts: 2,010
Likes: 3
From: Moon Twp. PA USA
Originally Posted by ZO SIC
I searched a few different times and did not come up with anything...
So, what is the proper way to adjust the Z-bar clutch setup?
Does anyone have pictures of how the linkage and hardware is installed? And where their clutch return spring is?
So, what is the proper way to adjust the Z-bar clutch setup?
Does anyone have pictures of how the linkage and hardware is installed? And where their clutch return spring is?
Thread Starter
Racer
Joined: Oct 2001
Posts: 385
Likes: 3
From: Lincoln CA
Originally Posted by glen242
What kind (brand) of clutch?
The TOB I removed from the car (with the Centerforce stage 2 clutch) was longer then this new TOB...
I crawled under the car while someone operated the clutch and the clutch fork is NEARLY touching the firewall... I might be able to slip a few pieces of paper between the two.
And the firewall is cracked from where it has contacted in the past (from my Z-bar bracket being shimmed towards the firewall in the past.)
A friend looked at the car today and remarked that my clutch rod (through the firewall) didn't look factory/stock.
Is there any adjustment on the clutch pedal itself? Up under the dash?
It seems like I only need another 1/4"-1/2" of throw on the clutch to operate properly, but there is no more adjustment or room for the clutch fork between the firewall.
Stock GM alluminum bellhousing, and "stock" clutch fork. Non adjustable pivot ball (from what I could tell.)
Can you swap or adjust an adjustable pivot ball with the entire assembly (clutch/bellhousing/trans/engine) assembled?
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Pro
Joined: Sep 2004
Posts: 595
Likes: 0
From: Boston MA
Bad news... You have to remove the transmission to replace the pivot ball. I think you have too much space between the throwout bearing adn the fingers. The solution is that you have to replace the pivot ball with an adjustable one. (more bad news)
Sorry,
Joe
Sorry,
Joe
Advanced
Joined: Sep 2005
Posts: 74
Likes: 0
From: Seattle WA
I had the same issue after a clutch replacement and discovered that bubba at the shop didn't have a clue about clutches and had to remove the gearbox again and replace the pivot ball and clutch fork. This should have been done when the clutch was replaced but no one told me this might be worn. So I learned to replace all components when doing a job to do it right.
-Mark
-Mark
Thread Starter
Racer
Joined: Oct 2001
Posts: 385
Likes: 3
From: Lincoln CA
Originally Posted by 68coupe
Bad news... You have to remove the transmission to replace the pivot ball. I think you have too much space between the throwout bearing adn the fingers. The solution is that you have to replace the pivot ball with an adjustable one. (more bad news)
Sorry,
Joe
Sorry,
Joe
So, is there any set way to measure this stuff prior to installation to figure these quirks out?
How do I know what size/length of pivot ball to buy?
And why does the tranny have to come out? I can't remove the clutch fork through the slot in the bellhousing? I know I couldn't get the clutch fork off the pivot ball even with the bellhousing in the worktable...
