1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Rear Brake Issue/Questions...

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Old 10-29-12, 11:46 AM
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Rear Brake Issue/Questions...

So I'm replacing my rear pads on my 83, started on the passenger side and noticed a small puddle under that wheel of brake fluid...

I don't see any leaking from the actual caliper, but I am guessing the e-brake area? I'm not quite sure what I'm looking at, it's different than I'm use to.

I don't drive this car much as it's a race car, at the last event on the final few laps I noticed a grinding sound when I would trail brake, then a lot of the time. Checkered flag came out, I thought it was just bad pads (the rears are indeed CHEWED up so...), yesterday I drove it around just to check things as we're racing next weekend, that grinding noise appeared again.

Today I see the puddle. I'm not sure if they are related or not, my pad is literally chewed up, so it could just be that.

The issue I'm having:

1. The puddle...

2. How do you get the rear cylinder in for new pads??? I've pushed and pushed and it won't go in any further, is there a secret?

I haven't looked at the driver side yet, is the e-brake on both back wheels? The puddle is worrying though and it's not coming from the actual brake line to the caliper.

I have a Haynes manual but for some reason it doesn't include rear disc brake setups.
Old 10-29-12, 01:02 PM
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Found how to get the piston in (twist it lol).

I believe the leak is coming from the seal around the piston, possible? It's damp in here, can I replace just the seal or do I need a whole new caliper?
Old 10-29-12, 02:01 PM
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Seems like replacing the whole caliper in one is easier than rebuilding it.

There's always something!
Old 10-29-12, 03:37 PM
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Replacing is always faster and easier than rebuilds, but at a cost to the wallet. I just had my 82's calipers all rebuilt at around £180 (new seals and pistons, an "as new" rebuild). All 4 were badly seized.

As long as the caliper body is in good shape, i.e not seriously corroded or cracked even paying a professional to rebuild it would probably be less than a brand new one (for the same, maybe better outcome if they paint it to boot). That or buy a kit and do it yourself for even less, if you have the time to do so and confidence in your ability to then race on a home rebuilt caliper!

A handy hint getting pistons in - I find using a g-clamp can help get the last of the travel out of a caliper. Best bet is take it off completely and put the caliper body in a bench vice before using the g-clamp

Hope that helps.
Old 10-29-12, 04:11 PM
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Yeah I don't really trust/have the tools to rebuild it myself after looking it up. I can't really afford to mess up either it's suppose to be on track at 8:30am Thursday. lol

Best price for new I've found is $150ish for both rear calipers.

It sucks...I have two brand new front calipers. lol
Old 10-29-12, 05:45 PM
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Is there anyway just to rebuild the front section? Or does it all sort of work together?
Old 10-29-12, 06:40 PM
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its easy, really. look it up on a thread. is it leaking from the front or the back? i never rebuilt the rear on mines because they never leaked from the boots, if its just from the piston seal replace it and drive off into the sunset. remove the caliper completely and put in on a bench and use a vise to hold it while you work. it doesnt take long. unless you got a $80++ to buy a part that is in short supply then by all means go ahead.

i only replaced one of mines and that was becasue it was locked up completely and didnt want to wait a day to soak it and all that plus it was a front which was WAYYYY cheaper than a rear caliper. GL

https://www.rx7club.com/1st-gen-arch...lipers-855449/

i wouldnt mess with rebuilding the rear of the caliper unless you absolutly had too.
Old 10-29-12, 08:00 PM
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Originally Posted by Rotor_Venom08
its easy, really. look it up on a thread. is it leaking from the front or the back? i never rebuilt the rear on mines because they never leaked from the boots, if its just from the piston seal replace it and drive off into the sunset. remove the caliper completely and put in on a bench and use a vise to hold it while you work. it doesnt take long. unless you got a $80++ to buy a part that is in short supply then by all means go ahead.

i only replaced one of mines and that was becasue it was locked up completely and didnt want to wait a day to soak it and all that plus it was a front which was WAYYYY cheaper than a rear caliper. GL

https://www.rx7club.com/1st-gen-arch...lipers-855449/

i wouldnt mess with rebuilding the rear of the caliper unless you absolutly had too.
I thought it was leaking from the rear, but couldn't tell. After looking at it closer it seemed like it was leaking from around the piston.
Old 10-29-12, 08:44 PM
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Do I just pretty much follow the first steps and ignore the rear?

I found this guide as well searching around:

http://www.google.com/url?sa=t&rct=j...LaC3ayYPzQxU8A
Old 10-29-12, 08:56 PM
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My rear brakes weren't really giving me any problems, but the dust boots were torn . . . and I had the rear axles out of the car . . . and I felt like I hadn't done anything on my baby in a while. So I rebuilt the piston portion. BTW -- there are some good vids on YouTube. In general, you're just removing the piston, square cut seal, and boot; cleaning everything; then installing the new rubber pieces with the same old piston. It took me about 30 mins, cost me about $15, and was generally very easy. The trickiest part was getting the dust boot to seat properly with the spring clip.
Old 10-29-12, 08:59 PM
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Originally Posted by elwood
My rear brakes weren't really giving me any problems, but the dust boots were torn . . . and I had the rear axles out of the car . . . and I felt like I hadn't done anything on my baby in a while. So I rebuilt the piston portion. BTW -- there are some good vids on YouTube. In general, you're just removing the piston, square cut seal, and boot; cleaning everything; then installing the new rubber pieces with the same old piston. It took me about 30 mins, cost me about $15, and was generally very easy. The trickiest part was getting the dust boot to seat properly with the spring clip.
Hmmm maybe I'll just do that then, I know my local parts store has rebuild kits on stock but not calipers, so it may be my only option.
Old 10-29-12, 09:14 PM
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its very straight forward. my best Freid for this job is a flathead screwdriver with the edges ground off. you can get it in the boot, or whatever and not rip it.
Old 10-29-12, 10:22 PM
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I agree, the caliper rebuild not very complicated, and you don't need all the specialized tools they'll show you in a video. That being said, I haven't done my rears yet either (didn't need it when I did the fronts, haven't gotten to it now because of kids and stuff. It's on my winter list)
Old 10-30-12, 08:09 AM
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Looks like I'm just going to buy some new ones. I don't want to risk not doing it right or not finishing it in time, plus we're racing it in a 3 hour enduro and would hate to DNF because of that.
Old 10-30-12, 08:28 AM
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i rebuilt 6 rx7 calipers, 2 rears and 4 fronts. ITS SO EASY. you pop the old piston out, throw the boot in the garbage, throw the seal in the garbage, then install the new seal and boot using brake fluid as lube. simple.

Its so cheap and easy, that the first time i do brakes on any new (1980's) vehicle i just rebuild the calipers too. IMO cheap insurance.
Old 10-30-12, 02:34 PM
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Originally Posted by cshaw07
i rebuilt 6 rx7 calipers, 2 rears and 4 fronts. ITS SO EASY. you pop the old piston out, throw the boot in the garbage, throw the seal in the garbage, then install the new seal and boot using brake fluid as lube. simple.

Its so cheap and easy, that the first time i do brakes on any new (1980's) vehicle i just rebuild the calipers too. IMO cheap insurance.
Is that just for the front half?

What if I don't use the e-brake at all, if it was leaking back there would that still be an issue?

I may have to rebuild now, the parts store ended up not having any available until Friday or so, they said this afternoon, didn't work out. Running out of time!
Old 10-30-12, 09:55 PM
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Decided to rebuild the front side of the caliper, the seal did look torn so hopefully that was the leak. Not too bad, just getting that spring clip in took me forever.

Another quick question...those small metal clips that hold the pads. Do people keep those or throw them out? I've seen a few people say they toss them, but my pads have some play. Is it the lack of those or does my piston need another half turn?

I still have the clips but wasn't sure if I should put them back on or not they just fell off, I haven't driven the car and need to bleed the brakes tomorrow so it wouldn't be a big deal putting them back on.
Old 10-31-12, 10:51 AM
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Originally Posted by Simon Tibbett
Another quick question...those small metal clips that hold the pads. Do people keep those or throw them out? I've seen a few people say they toss them, but my pads have some play. Is it the lack of those or does my piston need another half turn?

I still have the clips but wasn't sure if I should put them back on or not they just fell off, I haven't driven the car and need to bleed the brakes tomorrow so it wouldn't be a big deal putting them back on.
you actually WANT the play, in a race car everything will be HOT, and the last thing you want is a pad to stick.
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