92 calipler problems

[RSKBDK]

i put new pads and new rotors on the rear of my 92 sl2 4 wheel disk anti lock brake car , and i cleaned everything and replaced the clips and greased the pins , the car sat for a few months while i worked on it and then ran fine , i had to work on it again and it sat for 5 weeks again , when i drove it the rotors were rusted and the brakes grabbie , i thought after a few miles it would go away , but in stead both rear calipers locked up and the rear pads ate the rotors up ? ?? i took everything apart and i'm not sure if i should replace the calipers as they are not leaking and i got them to retract with a c-clamp but i had to release the zerk fitting ... should i be able to push the caliper piston back with just a c-clamp withpout releasing the zerk fitting ? and the piston only went back in if it turned counter clock wise ? how can i tell if i should replace the rear calipers and how can i check them ??? thanks bob

[mysatilac]

Sorry, I dont wanna make a new thread,
Is it ok to use brake pads that may have Tranny Fluid or MMO on them?

I had the box in the trunk of my last car, now the box is red from the spilled fluids, Maybe none on the brake pads themselves, but the box is red...
Can I use brake cleaner on them first or something?

[sierrap615]

Originally Posted by RSKBDK

i put new pads and new rotors on the rear of my 92 sl2 4 wheel disk anti lock brake car , and i cleaned everything and replaced the clips and greased the pins , the car sat for a few months while i worked on it and then ran fine , i had to work on it again and it sat for 5 weeks again , when i drove it the rotors were rusted and the brakes grabbie , i thought after a few miles it would go away , but in stead both rear calipers locked up and the rear pads ate the rotors up ? ?? i took everything apart and i'm not sure if i should replace the calipers as they are not leaking and i got them to retract with a c-clamp but i had to release the zerk fitting ... should i be able to push the caliper piston back with just a c-clamp withpout releasing the zerk fitting ? and the piston only went back in if it turned counter clock wise ? how can i tell if i should replace the rear calipers and how can i check them ??? thanks bob

using C-clamps to retract the pistions may have damaged the parking brake mechanisium. check the cables for binding, check the pins for binding. ensure the pedal is fully returning and you have no vacuum booster problems. bleed/flush the brakes. check the pistion seals. then i would replace both rear calipers. i beleave rebuilt units are around $15 each IIRC.

the pistons can be retracked without opening the bleed screws, however you should open the bleed screws or the seals inside the master cylinder or ABS may be damaged.

Originally Posted by mysatilac

Sorry, I dont wanna make a new thread,
Is it ok to use brake pads that may have Tranny Fluid or MMO on them?

I had the box in the trunk of my last car, now the box is red from the spilled fluids, Maybe none on the brake pads themselves, but the box is red...
Can I use brake cleaner on them first or something?

lazy....

i *THINK* you will be ok, use the brake clean, and buy some course emry cloath( i think i misspelled that, its like sand paper, but better in this case), and sand off the surface of the pads.

[RSKBDK]

thanks , the rotors were not eaten up , just rusted very bad , the car fail inspection because of too much rust and the calipers were locked up because of all this rust they couldn't free float , the calipers seem to work fine now that i cleaned everything up , but i couldn't get the rust off the rotors so i bought new ones 17.50 ea , but for loaded calipers thats the caliper with the pads and caliper bracket the cost is 137.00 thanks again bob

[mysatilac]

I went ahead and bought some new pads, $18, would've used the ones I had, but they didn't fit anyway,
New ones work good, spilled a little brake fluid in the engine bay while I compressing the caliper, but rinsed it off pretty good,
Installed 'em no more squeak when braking,
but I still do have the squeak when I accelerate, damn belt or tentioner...

[sierrap615]

hope the brake fluid didn't touch any paint....

[mysatilac]

No, It just slowly flowed outta the reservoir, and onto some hoses (including fuel lines) that'll be ok though since I rinsed it off pretty good/quick, right?

I siphoned off some fluid last time I changed 'em, but this time I removed the cap and thought I'd be OK...Thats what I get for thinkin
Also didn't have a C clamp, had to just squeeze with my hand but apparently I squeezed the piston into the caliper too quickly

[sierrap615]

you DON'T want to use a c-clamp

you DO want to open the bleed screws

[mysatilac]

Originally Posted by sierrap615

you DON'T want to use a c-clamp

you DO want to open the bleed screws

A C-clamp is how I always saw it done, and how I've always done it before, Is there a chance of damaging the caliper? if done correctly I dont see how since the piston can be flush in its bore, and thats as far as a C-clamp would let you go...

I want to open the bleed screw to let off fluid instead of siphoning? When I am compressing the piston or before?

:sigh:
Apples to apples...

[sierrap615]

the front brakes will work with a C-clamp, using a C-clamp on the rear brakes can damage the parking brake. not that is really nessiciary, i've always done it by hand.

put a clear hose on the bleed srcew(its easyer,cleaner, and less likey to let air in), open the srcew, push the piston in, then close the srcew(don't over tighten!)

[mysatilac]

Dont see how siphoning off the top would let air in, but that seems reasonable and easy enough to do, I'll try that next time, If I pull the piston in/out, and do that that would be the equivilent of bleeding the system correct?
I've got rear drum brakes, so I haven't changed them, nor have I found an indication that I need to, do they have a wear indicator that squeaks as a warning?

[sierrap615]

this does not count as brake bleeding in my mind, i'm sure others will tell you different.

i don't beleave there is a wear indicatior, other then measuring them.

[mysatilac]

But they dont wear out as quickly, correct?

[sierrap615]

no, they don't. more stoping power is giving to the front brakes, plus there are several other factiors, i have heard of many people with 100K miles have changed their front brakes three times and haven't touched their rear brakes.