I am putting on new rotors and pads, and I currently have the old stuff off, but cannot get the rear caliper to compress back to open so I can fit both pads on and get it to fit on the rotor. I am using a big clamp, and even a box end wrench as an extension to turn the clamp, but the piston won't go in. WHat can I do? I need about a 1/4 inch of movement.

Also why do the inner brake pads have those little bumps on the back in the middle, can I file them off to make it fit easier?

Help quick thanks!

The rear caliper pistons have to be turned back in. There is a tool to do this and I believe you can rent the tool from AutoZone.

Woa, weird, thanks!

Only 88 rear calipers should be turned in. The others compress in, but the parking brake lever must be taken off.

Looking at the '86 FSM and cannot see how the actuator screw for the parking brake would adjust without turning the caliper piston. What is the purpose of removing the parking brake lever? Does the adjusting screw turn on itself when the piston is compressed?

[This message has been edited by Hudini (edited 09-09-2007).]

Take the parking brake lever off and try it. It worked on mine.

Joe Crawford
Texas

Take the parking brake lever off and screw it in with the tool? I have the tool now. Mine is an 86 and appears to need the tool.

quote What is the purpose of removing the parking brake lever? Does the adjusting screw turn on itself when the piston is compressed?

See this page, and this page.

Removing the parking brake lever allows you to compress the piston and the piston then turns the internal screw. The approved method is to turn the piston and let the screw stay stationary. Two different ways of doing the exact same thing. Bottom line is the parking brake mechanism has to screw back into the piston for it to retract.

Yep, worked. That little nut on the parking brake mechanism was tight. After removing the nut and using the tool I could turn the piston back in clockwise. The stud that the parking brake mech was nutted to had to spin as I tightened, I don't see any way it was going to happen with that still attached. Thanks! Got my rear ones done today.

quote Originally posted by pswayne: Only 88 rear calipers should be turned in. The others compress in, but the parking brake lever must be taken off.

Ummmm..... no... I have to turn in mine..and I have an '86....

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'86 Fastback SE 5 spd -'94 HD Electra Glide Cassic -'99 Chevy K-1500 Z-71

quote Originally posted by pswayne: See this page, and this page.

Cool, good read. The actuator screw does (supposed to) turn on itself when the parking brake lever is removed from the caliper and the piston is compressed (not turned). As Formula88 said, 2 different ways of accomplishing the same thing.

quote Originally posted by pswayne: Only 88 rear calipers should be turned in. The others compress in, but the parking brake lever must be taken off.

The rears on both my 87's also turn in. ( and have to take the lever off too.. )

OK, had stuff all put back together and while driving noticed teh brkes aren't that great. The rears are doing nothing. Whats going on? I turned them in as said above in order to put the new pads on, but it seems the piston isn't moving at all on either rear caliper.

My front brakes seem to be doing all the work, and I tried on gravel hitting the brakes hard and the fronts lock up instantly while the back wheels just roll. Is there something you are supposed to do special, I have not had a car that required the caliper pistons turned in before like these were?

not trying to hijack at all but i have the same problem and my e-brake is diconnected at the back somewhere havent looked at it yet but help on this subject seems to be needed by a few ppl

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The Devil/El Diablo

My Cardomain
My Photobucket(pix of my car and things i hope to add)

The E Brake adjusts the rear brakes. By turning them in you have too much clearance now for them to work properly and they need to be adjusted. Go to Ogre's Cave and look for brakes under body and chassis. A link to the cave is also at the top of the page. If you follow the instructions there you should be able to get your rear brakes properly adjusted.

John Stricker

quote Originally posted by 2.5: My front brakes seem to be doing all the work, and I tried on gravel hitting the brakes hard and the fronts lock up instantly while the back wheels just roll. Is there something you are supposed to do special, I have not had a car that required the caliper pistons turned in before like these were?

Thanks, I thought there must be some screwing back in or something I need to do. Although they fit real tight on there with no visible clearance. I'll check out the link and see, maybe I need to tighten the nut on the back.

P.S. My ebrake didn't seem safe to use so I disconnected it as well, while redoing my brakes.

just pull the parking brake while you have your foot on the pedal. you may have to do it a couple dozen times but that is how you adjust the rear brakes. cycle the brake pedal and parking brake. you must hook you cable back up or do it by hand back at the caliper.

Well I disconnected the E brake because it wasn't working anyway, would the procedure just be: put teh Ebrake lever back on and pull it back and forth while the wife pumps the brake pedal? Car running I assume?

Thanks so far

Reminds me of a quote from Shawshank Redemption: "Mr. Hadley, do you trust your wife?"

If the ebrake doesn't work properly, wouldn't it be better to spend the twenty bucks and buy a cable to replace the cable that is bad?

Or if it's the calipers that are bad, which is usually the case, due to lack of use. You might need to rebuild the caliper to get your ebrake to work properly again.

So you pretty much need a functioning Ebrake in order to change your rear pads, and have them work?

quote Originally posted by 2.5: So you pretty much need a functioning Ebrake in order to change your rear pads, and have them work?

Yes.

I may have a seperate problem? I was trying to see if they are working in back, by having it on jackstands, wheels off, and running it in 1st gear, then applying brakes. The passenger side rotor stops spinning instantly, but the drivers side actually speeds up when I apply the brake. I assume this is because it transferred the driving power to the drivers side when the passenger side stopped. How can I do a real test?

Also, I see the rear disks are dark colored where the pad rubs, it fit that tight, they must be lightly rubbing while driving, its not enough to slow the car down while rolling even on a very slight incline so I can't imagine it was bad, could it have ruined the pads and how could I tell?
I am now wondering if the brake calipers function ok but the pads were cooked and have no stopping power?

If you cannot compress the piston with the brake lever removed, you have a bad caliper and it should be replaced. If you have to remove the brake lever to screw the piston in, you have a bad caliper and it should be replaced.

The internal caliper parts are probably locked together like a jammed nut on a bolt, most likely caused by trying to compress the piston without first removing the lever.

Note that the lever is the only thing preventing the splined shaft from rotating into the piston when the lever moves in the release direction. You can try replacing the lever with a large washer and attach a flat wrench to the hex of the shaft with the retaining nut. Turn the wrench in the direction that would cause the piston to retract until the shaft turns freely. If it doesn’t, the caliper is a lost cause.

Next, turn the shaft in the operate direction till the pads touch the rotor. Reattach the lever in a position that is about 1/4" off the return stop if possible. A little more is OK but less is not. Then reinstall the lever spring (not the cable) and “snap” the lever against the stop a few times until movement of 1/4" or less off the stop will lock the rotor. The lever should freely return to the stop by pressure from the spring. If this works, the caliper is adjusted and will work for a while till the pads wear some. edit: Reattach the cable. You need an operating hand brake that is used often to keep the pads adjusted.

Also, don’t file off the “bumps” on the pads. They are there to keep the piston rotating when the e-brake is applied. The tool you used to rotate the piston into the caliper is used to line up the holes in the piston with the bumps on the pad.

[This message has been edited by spark1 (edited 09-21-2007).]

Wow. Do any shops know how to do this? I give up. I can't believe how complicated that is, thanks for the info though. If anyone out there lives in MN and knows how to do this I will pay you to. Or if you know about any shops that are good with Fieros.

[This message has been edited by 2.5 (edited 09-21-2007).]

ok so whats this special tool to get this working? sorry I may have missed it somewhere in the thred

Did you bleed the rears when you were done with installing the caliper back on?
When you remove the e-brake nut and lever air can enter the caliper.

Hey guys I had my rears done at a shop. My Calipers needed replacing. If you saw and heard rust particles crunching when you turned yuors in you may need new ones too. The tool to turnm them in is available for use at Autozones for a returnable deposit. My Ebrake cable needs replacing too, if your Ebrake does not function properly, you may not be able to get your rear brakes working without replacing teh Ebrake cables first.

bump, so i can save it.

I just use Channel locks, ( monkey grips ) to rotate the piston inside the rear caliper, I think turn couterclockwise, I forget but you will be able to see if they are going in. just be careful not to chew up the seal.

quote Originally posted by 2.5: OK tell me what I did wrong...

See your own first post:

quote Originally posted by 2.5: I am using a big clamp, and even a box end wrench as an extension to turn the clamp, but the piston won't go in.

quote why do the inner brake pads have those little bumps on the back in the middle, can I file them off to make it fit easier?

No. The bumps are there to keep the pistons from turning during normal operation. Don't file them off.