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SRT17
11-13-2014, 05:40 PM
I am trying to get my clutch working. The clutch worked when I took my car apart last year. I have a zoom street stock clutch, CNC pull type slave cylinder, Wilwood ? master cylinder and new clutch fork. The problem is... I have to have the throw out bearing against the fingers ,all the time,( No play in fork) to get the clutch to disengage. I have bleed it over and over. I have taken it apart 3 times checking everything. The clutch works fine once I get it that tight. Could the master and slave cylinders be worn out? What am I missing? Thanks

Racer96m
11-14-2014, 11:10 AM
Sounds like the clutch fork you replaced is not correct, or uses a different pivot ball height.

Dave

dirtplay18
11-14-2014, 11:56 AM
Slave cylinder may not have enough travel for your application. Are you allowed to run a hydraulic release bearing? They work out nice.

SRT17
11-14-2014, 05:22 PM
Had the problem before I changed the fork. Every thing is as it was set up before. The new fork is the same as the old one. The old one had the tabs worn some so I changed it, thinking it was the problem. We can run the hydo bearing. I don't know anything about them.

72Dubya
11-17-2014, 09:38 AM
The hydraulic bearings make life so much easier. I would definitely recommend one, the extra money is worth it for as much less hassle you have. You will regret using anything else if you do switch. Tilton makes really nice ones, very dependable.

Pigpen52
11-17-2014, 02:16 PM
Hyd throw out bearings are the worst... I only use the pull type slave cylinder....the problem is...not enough travel. So, to fix that problem, I move the pivot point. I cut the fork right at the end of the bellhousing, weld a piece of 1" flatbar over the part I cut, drill a hole in it, put a 3/8 hiem on the slave cylinder and bolt it to the fork. This will bring the part the slave cylinder bolts to closer to the pivot, thus requiring less travel.

Pigpen52
11-20-2014, 11:17 AM
complicated? I have used this system for years...with zero failures...one is over 14 years old. Look at the amount of travel required...mounted in the stock location a slave cylinder just barely releases the clutch...so you have to run it to tight for it to work. takes about 30 min. to modify the fork. Seems pretty easy to me. and if it ever fails....which I have not seen...all the linkage is outside...so you don't have to pull the transmission to fix it like a hyd. bearing. And...to adjust...you don't have to pull the transmission either....seems very simple to me. I have had a couple of hyd. bearings...all failed at some point and needed new o rings.... and the cost is way higher than a pull cylinder

dirtplay18
11-20-2014, 11:42 AM
Hey stock car, I've used the same idea with the fork before, with the addition of an old rocker arm pivot ball on the front (dished) side of the fork. Seems to help keep the slave from binding. Hydro release bearings are deff the way to go, may have to get a shim kit for it.

SRT17
11-20-2014, 08:10 PM
I have found out the clutch fork pivot ball depth is off. I have ordered a longer stud to put in. That doesn't explain why it worked for 3 years. I will try that before I go any further. I also use just a threaded rod.

SRT17
11-21-2014, 06:34 PM
I got it all back together today with the longer stud. Still the same problem.....

SRT17
11-21-2014, 08:42 PM
I dont want it touching the fingers. It didnt before I took it apart. But now it will not work without it. I think the master and slave are week. I have the car on jack stands now. With the car running it will not go in gear. I can tighten the fork up tight, with the TO bearing against the fingers, it works. Doesn't matter if it is on the ground or in the air,same thing. With it running I push the clutch and brake at the same time the car dies. So I know it is not releasing. The clutch is in the right way. Can only go one way on mine...LOL....I think I need a 7/8 bore master( has 3/4 now) and a new slave....

SRT17
11-21-2014, 09:23 PM
It only moves about 5/8" with it hooked up and not. Not sure what it was before, never checked it, just set the play. If I turned the clutch backwards, the springs hit the flywheel and there is a 1/4" gap between it and the flywheel.

SRT17
11-22-2014, 09:25 AM
Could it be the pressure plate? It looked good all the times I put it in....LOL Maybe something wrong with it?? But like I said before... If the TOB is against the fingers everything works. To me it just doesn't have the pull and adjustment it needs or had....

Pigpen52
01-02-2015, 07:57 AM
I always had that problem till I moved the pivot....takes 30 min. and will stop all your problems... although...I did read on some slave cylinders they move more than 3/4" for this reason. I usually run speedway cylinders cause their cheap. I did install a cnc cylinder recently...it seemed to have even less movement than the speedway cylinder. Im sure stock car driver thinks Im an idiot....but...I have been racing for 25 years...and have done this simple repair a lot of times....heck..I even moved the pivot ball to the right side of the bellhousing and did the same thing to make it simpler to work on.... took about an hour to modify the bellhousing...but on cars with a stock floorboard, its a lot easier to work on.

Hurst390
01-02-2015, 07:32 PM
How big is the diameter of the piston in the master cyl? you might need a different master with a bigger piston...

Pigpen52
01-05-2015, 07:45 AM
Size of the master cylinder does not change how far the slave cylinder moves....just how quickly... most clutch master cylinders are 3/4 " I have one with a 1" the clutch pedal is much harder...but only moves a few inches, compared to my other cars with 3/4 master cylinders.

SRT17
01-19-2015, 08:04 PM
Got around to working on the car.... New master and slave cylinder and longer stud... Problem solved....