No parking brake?

[infernosg]

I finally got around to finishing the brakes over the weekend. I had purchased rebuilt calipers from Rockauto a while back.

After finishing everything I noticed no matter how much I adjusted the parking brake the lever was very easy to pull. Turns out the parking brake on the passenger side is not engaging. The cable pulls, the lever rotates but the piston doesn't move in the caliper. Normal hydraulic actions works just fine though.

My understanding is something is wrong with the self-adjuster in the caliper. Not having a parking brake on that side isn't a big deal but I'm curious if this will cause other brake problems if I don't fix/replace the caliper.

[FC Zach]

This issue happened to mine once before as well as only one wheel engaging, I bled the calipers and had no further issues. It's been years since worked with this but I believe there were two bleed screws and I opened the upside-down one on the bottom, I remember that because it didn't make any sense to me.

Anyways I figured this all out after needlessly replacing a caliper that ended with the same results as before. Looked into it and it was too simple :banghead:

[infernosg]

This issue happened to mine once before as well as only one wheel engaging, I bled the calipers and had no further issues. It's been years since worked with this but I believe there were two bleed screws and I opened the upside-down one on the bottom, I remember that because it didn't make any sense to me.

Anyways I figured this all out after needlessly replacing a caliper that ended with the same results as before. Looked into it and it was too simple :banghead:
I thought the parking brake was purely mechanical.

I never understood why the calipers have two bleed valves. Ironically, the passenger's side is the only one I attempted to bleed with the bottom valve out of curiosity. I still bled both rears with the top screw but hopefully it's coincidence that the passenger's side isn't working. I've probably bled the whole system 5 times now with a Motive pressure bleeder and the traditional 2-person method and no luck.

[FC Zach]

I thought the parking brake was purely mechanical.

You would think!

I'll double check my manual, I could be wrong.

[Pete_89T2]

Interesting... I thought the bottom bleeder screw was there simply there to help purge accumulated crud out of the caliper when pressure flushing & bleeding. Given the way this caliper is designed and oriented on the car, you can see there's a low point that would tend to trap & accumulate crud, so I figured the extra bleeder was there to deal with it.

Whenever I flush & bleed brakes on the FC, for the rears I open the bottom screw first (top closed) to flush out the crud. When fluid flows out clear & clean from there, I close the bottom screw & open the top one to purge the air out.

[FC Zach]

Double checked my manual and found this but nothing in detail regarding why the bottom is used. .

[RETed]

Interesting... I thought the bottom bleeder screw was there simply there to help purge accumulated crud out of the caliper when pressure flushing & bleeding. Given the way this caliper is designed and oriented on the car, you can see there's a low point that would tend to trap & accumulate crud, so I figured the extra bleeder was there to deal with it.

+1

I agree - it's due to the orientation of the brake caliper being almost vertical.


-Ted

[infernosg]

Double checked my manual and found this but nothing in detail regarding why the bottom is used. .

Interesting. Is that in the Haynes manual? I have a paper copy of the FSM and I don't recall seeing that. I'll give it a try because I definitely fall into the category of having "overhauled" the calipers. The worst that can happen is the parking brake still doesn't work. I've discovered some older RX7 racecars have deleted the parking brake system so I'm not too concerned at this point.

EDIT: It shows up in the FSM for the '88 MY but not in the FSM for the '89 MY. More interesting...

On a somewhat related topic does anyone know how to actually adjust the brake pedal "free play?" I've swapped to the 929 MC and booster and the pedal free play is out of spec according to the FSM. The FSM instructions for adjusting pedal height and free play are the same. In order to get the free play in spec I have to adjust the brake pedal all the way out, which puts the pedal height out of spec. I don't see how to get the free play in spec without violating the pedal height spec. Maybe the 929 free play specs are different...

[FC Zach]

Yes, it's a Haynes manual.

[infernosg]

Yes, it's a Haynes manual.

Yeah, weird that it's in the Haynes manual and the S4 FSM's but not in the S5. I'll give that a try. I've also read that a good hard brake from speed in reverse can also dislodge a stuck self-adjuster.

I still can't find anything about independently adjusting pedal height and free play. I currently have free play set within spec but having the pedal all the way out against the stop, which "pre-loads" the booster pushrod to an extent.

[infernosg]

So fast forward 6+ months and I'm still diagnosing the problem. I learned something new today: with the piston pushed all the way into the caliper both sides appear to work as normal. That is, rotate the lever and the piston is moved outward about 1/8 in. or so. However, after the piston is adjusted outward to contact the brake pad only the driver's side piston moves when the parking break lever is moved. I'm guessing something is wrong inside the passenger's side caliper.

[RETed]

I'm guessing something is wrong inside the passenger's side caliper.

+1

I agree something is wrong with the rebuilt unit...

Is the unit still under warranty?
If not, why not tear it apart and inspect the bore?


-Ted

[infernosg]

+1

I agree something is wrong with the rebuilt unit...

Is the unit still under warranty?
If not, why not tear it apart and inspect the bore?


-Ted

Yep, bad caliper. Replaced it with another reman'd unit and everything functions as it should. Too bad the left rear is now leaking so it needs to be replaced (again) as well. I'm going with Centric rebuilds units this time. I've had good luck with them in the past.

[TitaniumTT]

I've never under any circumstances had any luck with anything that suckauto has ever sent me.... They're horrid.

[infernosg]

I've never under any circumstances had any luck with anything that suckauto has ever sent me.... They're horrid.

I don't have any issues with RockAuto themselves - they're just the distributor. I think the current/bad units were reman'd by Raybestos. The re-replacements are Centric and so far no issues with the right rear (no leaking and the parking brake works). I think the fronts were Centric as well and they seem to be holding up just fine. If they bugger up again I'm buying rebuild kits and doing it myself.

[TitaniumTT]

They've never managed to get a single order right for me. And their website is inaccurate as well. As in they have parts on their website that they say will fit, when in reality they don't. And then they expect me tp pay for their fuck up in the form of return shipping costs. No.. Absolutely not. They can go fuck themselves.

[FC Zach]

Exact same thing has happened to me and on multiple occasions. +1 for the advertising parts that don't fit! That's a website that you have to be absolutely sure about what you need but even then I've come across stuff with incorrect pictures. . . I have never been so frustrated with something that should be a simple process, I haven't ordered from them since. If I do order anything in the future, it'll be something I'm familiar with.

[infernosg]

Weird, I've never had any problems with the brake stuff I've ordered being the wrong P/N or not fitting. What parts did you guys have issues with so I know to steer clear?

[TitaniumTT]

Exact same thing has happened to me and on multiple occasions. +1 for the advertising parts that don't fit! That's a website that you have to be absolutely sure about what you need but even then I've come across stuff with incorrect pictures. . . I have never been so frustrated with something that should be a simple process, I haven't ordered from them since. If I do order anything in the future, it'll be something I'm familiar with.

Yup! I'm fine with it, mistakes happen, but fucking OWN UP TO IT! And NEVER make the customer pay for your mistake.

Weird, I've never had any problems with the brake stuff I've ordered being the wrong P/N or not fitting. What parts did you guys have issues with so I know to steer clear?

:lol: Everything!!

Two perfect cases are Alternator for my '98 Jeep. They had one listed that was hi-output. So of course I bought it. When it showed it didn't fit. After going back and forth with them saying something about a tow package or something and that's why it wouldn't fit, they wouldn't take it back without me footing the return shipping charge, and a re-stocking fee. So before I did that I called my Jeep guy and we went through every single option of Jeep that was available that year and every single one of them had the same alt bracket. So it wouldn't have mattered, it never would've fit. When I told them their system was fucked they wouldn't admit it.... which leads to the next example

On that SAME MOTHERFUCKING ORDER I got a fel-pro rear main seal for the 2000 Jeep I also own (and for the '98 as well). Right on Fel-Pro's OWN FUCKING PACKAGING OR DESTRUCTIONS it says, different seals for 2000 and later 4.0's blah blah blah. Well... the asshats shipped me two of the same, and on their website the part numbers are the same as well. So again, their massive fuck up for not have the right parts listed and again, they wouldn't take it back without me paying for shipping and a restocking fee.

RockAuto can seriously go fuck themselves.