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How hard is it to change out the clutch master cylinder. Have any of you guys replaced one? I read on the net you have to remove the brake master cylinder and booster, isnt that hard plumbed?
 

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I removed my old master and installed a Tick master today. If you download the Tick instructions, you'll see they don't recommend removing the brake booster. See:

https://www.tickperformance.com/content/GTOInstructions.pdf

It's an interesting challenge. I did buy a cheapo ¼” air ratchet from Harbor Frt for this job, and that helped a bit, but only inside the car, not under the hood. Remove the horn with a T30 Torx bit that has a center hole in the tip. If you have a T30 without a hole, you need to buy one with a hole before you get started. I had to unhook the wire looms near the booster and shift them around to gain room. The brake booster will move enough toward the engine if you pull the studs all the way out of the firewall and push it inboard. You will need to put the booster back in normal position to release the clutch pipe joint that is under and inboard from the booster. Study this quick connect joint carefully to know where the two pieces separate - memorize the layout of the duplicate joint screwed to the bell housing. After that you will have to pull the booster back out again to continue. The booster was easy to get back in the firewall. The studs will be visible from inside the car and will show which way to tilt the booster, if need be.

The fender well is in the way big time, so I used 1/4" drive long extensions and U-joint for the master cylinder nuts. I bought a flexible extension for this job from Sears, but it didn't help - too stiff. Just keep trying with the U-joint.

One brilliant thing I did to re-install the bottom nut that you almost can't see onto the master was to put the nut in the tip end of a 3" or 4" long piece of 1/2" dia clear plastic tubing and anchor the nut in the tip by piercing both side walls for a piece of toothpick. Worked good.

Be sure to remove the air bag fuse per the FSM. The FSM wants you to disconnect the air bag module too, but I didn't. Remove the fuse panel door under the steering wheel by undoing a few screws and pulling the top edge from the latches. And disconnect the battery, because the brake lights will come on when the booster is moved forward. Don't jack up the car until you need to get underneath for removing the lower part of the two-piece clutch pipe. Once the car is up, you'll need something to stand on.

The replacement Tick flex pipe needed to be re-routed several times to find the best spot that is as far away from the exhaust manifold as possible. It needed to go under the steering shaft. Contrary to the Tick instructions, I found it necessary to attach the flex pipe to the master before installing the master. Be careful that some Tick parts are screwed together but not tightly, such as the quick connect joint to the flex pipe. Try installing the Tick master with the black aluminum spacer already on it, contrary to their instruction. If the master will fit on the firewall studs with the spacer attached, then remove it and bench tighten the master to the spacer and bench add the extremely tight fitting white plastic cover before tightening the spacer to the firewall. For lubrication, dampen the ID of the cover with the same brake fluid you'll add later. If the master/spacer will not go on the studs with the spacer attached, then you will need to attach the spacer to the firewall first, the master second, and you'll need a 3/8" drive crow's foot x 1/2" to tighten the upper nut before attaching the cover - access to the top nut is blocked even before the cover is attached.

I had never bled the clutch hydraulics and was stumped where the bleeder valve is. There are 2 rectangular holes in the bell housing, one that you can see, and one that you can't. Directly above the hole with the clutch pipe in it is another hole for the bleeder, that you can find only by feel. I used an 11mm short socket. The FSM was no help in finding the bleeder but actually does show both holes in the bell housing if you study the drawings carefully under Clutch Housing Replacement. The rear edge of both holes is the bell housing to transmission interface.
 
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