More brake problems...

[MO-KAN SHO]

I've gone through the search on this subject, but couldn't find a cut and dry answer...

My RR brake caliper apparently hasn't been grabbing the rotor for some time as the rotor is rusty.

I'm planning on bleeding the brake system, as it probably hasn't been done for WAY too long.

I'm expecting to find something either blocking the caliper from closing, or some kind of problem in the brake line to that corner. Is there anything else I need to investigate?

TIA...

Ben

 

[rangerj]

MO-KAN SHO,

Some possibilities;

First check the slider pins. This would seem to be the most likely cause of the condition you describe. The pins are probably rusted and not allowing the caliper to adjust for brake pad wear.

If that is not ot look into the following;

Piston stuck in the caliper bore, (usually sticks and will not allow the piston to retract causing premature brake pad wear). (opposite of your situation )

Rubber brake line degraded on the inside and swollen shut, thus no pressure on the affected brake. (maybe)

Piston in the proportioning valve stuck, shutting off fluid to that line, (least likely)

Without more information I can only guess and tell you what I would look for. Let us know what you find. Keep in mind that your problem could be a combination of any of the above. rangerj

 

[MO-KAN SHO]

Well, I came out to my grandparents place in order to work on the car this weekend. (The apt complex would throw a fit if I did it there).

On the way down here, I rolled through town with the rear passenger window down, trying to listen and get a better idea of what's happening (or not).

If I hold the brakes, like coming to a stop from speed, I can eventually hear the rough grinding sound of the pad rubbing the rusted rotor, but not right away, it's like it's delayed.

Also, when I let off the brake, it continues grinding for a couple of seconds, like it's not releasing right away... also a delayed reaction.

So at this point, my starting point will be checking the brakeline on that corner. My train of thought is that if that line is partially blocked for whatever reason, the fluid would take longer to get to and from the piston creating a delayed response to that caliper.

Anyway, I still haven't taken it apart, that comes first thing in the am. (Gparents conned me into going out for dinner... damn the luck...

I will post whatever I find on here, and see what kind of input I get. =)

 

[MO-KAN SHO]

And where is this proportioning valve you speak of. I did see this mentioned as possible causes in the search I did, but from what I understand it's typically a reliable part and no one said where it is. I'm assuming on the brake line somewhere?

 

[rangerj]

Follow the brake lines from the master cylinder. You will find a metal block where the brake lines converge (not the ABS). rangerj

PS How was dinner?

 

[projectSHO89]

The proportioning valve is located above the left rear control arm (I forget whether is the front or rear one, just look).

Steve

 

[MO-KAN SHO]

Okay, so far here is what I've found.

The slider pins are apparently rusted solid to the bracket they slide into. I was able to get new slider pins at O'Reillys, however, they couldn't help with the bracket.

Because the slider pins were not moving, the pads were making contact on the inside of the rotor, but not the outside, allowing the outside of the rotor to rust away. With just one pad stopping it, that pad wore out quicker, and all the way down to the rivets and scoring the inside of the rotor far enough the rotor was no longer usable.

So now I'm in the middle of a brake job, got a new rotor, new pads for both sides, and new slider pins.

We're trying to break the old slider pins free, but it doesn't look likely. So if anyone has a bracket laying around...

Also, once I got to the point where I thought I could take the rotor itself off, I found the rotor was stuck pretty solid. I checked both the helms, and the chilton, and both said to remove two retainer nuts before removing the rotor. We thought the retainer nuts were that funny looking thing in the middle of the rotor.

Turns out that funny looking thing was the spindle nut, which we destroyed trying to take off. Now I have one of those on order, too.

When they were talking two retainer nuts, what the **** were they talking about? I can understand the Chilton being wrong, but the Helms, too?

I have not checked the brake line, yet... still plan on... These are just problems we found while disassembling. I am reasonably sure the brake line is okay since we found the slider pins in such bad shape.

 

[Rob94]

I could be wrong, but I believe Autozone has the brackets.

 

[MO-KAN SHO]

Thanks, Rob.... I'll check into that... thumb

 

[LaTechSHO]

my o'reilly store keeps the ones for the 89-92 in stock.....

the 93+ are overnight order... and you live in kansas city...which is the location of one our biggest warehouses.... its available... check my parts database for the numbers.... they are right at $20 and come with the slider pins and boots already installed


Louis

 

[MO-KAN SHO]

Your database is now listed in my Favorites...

Nice job on that... helps a lot.

Thanks again, guy... =)