[rkeysor]

This is further to my post about my clutch master cylinder torquing to the side when the pedal is depressed. There is a fracture in the firewall (viewed facing toward the rear of the car) from just below the right hand bolt retaining the cylinder and continuing down, as far as I can see, to about 6 a.m. I found it impossible to reach the inner mounting surface behind the pedals, despite removing the driver's seat for easier access. The clutch cylinder is difficult to access under the hood because of the intervening AC line, hydraulic, and electrical wires. In the best of circumstances, I would think the best fix would be to remove all of those lines, dumping the newly refreshed R12 in this car, taking out the clutch cylinder, and somehow welding in a plate or whatever. Among the problems is the wiring bundle running through the firewall at about 5 oclock and very near the the fracture. That looks pretty scary if welding is involved. I have installed a clamping system bolted through the wheel well wall (along with a couple of other fixes) that have stopped the sideways movement of the cylinder and restored the clutch pedal feel. However, observing the clutch cylinder from above (the panel over it removed) while the clutch is operated shows a barely perceptible forward cylinder movement. I had put JB Weld on the crack to see if it reopened, and it has not, but the forward movement, though slight, seems ominous. I'm thinking after 150,000 miles that clutch pedal has done a lot of repetitions. Anyone dealt with this problem?

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[flash]

it is a known issue, more common in east coast cars, and particularly with cars with the wrong pressure plate - many of the less expensive resellers are selling a plate that "fits" but has the wrong geometry, thereby increasing the load on the firewall

there is a brace available that prevents this, but the one to correct it is not yet done - it will be a couple of weeks yet before i can knock that out - i just haven't had time, and there has not been a lot of demand

there is a thread here about the other brace though, to give you an idea of the problem - search is your friend

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[rkeysor]

At Flash's suggestion I searched this topic and found the discussion of the brace he developed, along with a photo. My approach to attaching a brace entailed removing the inner fender lining and bolting my device with two 6 mm holes drilled alongside the clutch cylinder. It basically encircles the clutch cylinder and pulls it to the left (facing the front of the car), which in my car's case pull the cracked area back in alignment. I also generously covered the crack area with JB Weld and pressed a wooden wedge between the brake booster and the cylinder. l I couldn't agree more about the difficulty in working in this area, and I, too, had to constantly go under the car to recover nuts, bolts, sockets, etc. I think I used every tool I owned. I tried to get at the area from inside, first removing the driver's seat, but I couldn't get close to where the bolts for the clutch cylinder penetrate the firewall. As Flash indicates, exposing the area in the engine bay for work on the firewall means contending with an AC line, brake and clutch hydraulics, and, possibly more worrisome for welding, a large wiring bundle that passes through the firewall next to the clutch cylinder mounting area. Flash understandably was unable to photograph the area where his brace attaches to the cylinder or firewall, and, of course, it requires a specific strut brace for mounting. The seriousness of this condition was well documented by PhilG, who indicated it cost him $2,000 to have his welded up and repainted. Those of us dealing with this problem can all understand the difficulty of designing and actually installing the fix that Flash is contemplating. I thought it would be quite easy to install my fix, which while maybe unsightly, seems to work, albeit not stopping a slight forward motion of the cylinder when the clutch pedal is pushed, but it was a bitching nasty job.

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[AuthenticRestorations]

I had an 87 944 with two cracks on the firewall, both extending from the clutch master cylinder to below the brake master cylinder. Here is what I did to correct the problem.

1. Using I believe 16 gauge steel (Lowes or Home Depot) I cut out a piece which was simply bolted between the firewall and master cylinder.
2. To that piece I welded (mig) two brackets to the the strut tower. I removed the drivers side plastic wheel well during welding so as to prevent melting it due to the high temps.
3. Removed any welding slag and put some paintable caulk over the welds to prevent rusting.
4. Paint with matching paint.

Following the repair, I saw no firewall flex near the master brake cylinder or clutch cylinder.

The car was driving hard for years after that with no problems. If I encounter another car with the same issue I would not hesitate again to resolve the issue in the same manner. Time for repair if I recall correctly was about 2 hours.

Good Luck!

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[Seven30]

I did it the easy/expensive way, having a garage fix it. The cracks were so bad that the dash eventually had to come out, along with the pedals, brake booster, etc. The firewall was then welded, and painted at a paint shop. In addition to the cost of the repair, which I'm trying to forget, syncros and a syncro hub cost me big time. Not to mention that I'd replaced the master, slave and all associated bits and pieces because I couldn't find the clutch problem. The Design1 strut brace + firewall brace is on its way from RSBarn to prevent this happening again in the future.

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