brakes are getting stuck in closed position

[itsforandres]

the other night i took the car out for a spin. after a while,  i noticed the brake peddle was super stiff and i was hearing a clicking sound from the brakes when i was stopped. when i started to drive, it felt like the calipers were engaged and it smelled like pads, so i am assuming the pads were engaged. 

this is on an r33 gtr. does the power steering system provide the vacuum for the brakes? does this sound familiar to anyone?

 

thanks in advance. 

[The Bogan]

Sticky caliper pistons?

Booster has nothing to do with binding brakes

Might need a rebuild, maybe?

Have a look at the discs, you should be able to tell which caliper is sticking 

If one is sticking, rebuild them all

Youtube is your friend for how to rebuild them

Or, your handbrake cable is to tight and needs adjusting or hung up on something, pull the wheels and find which brake is binding

[itsforandres]

these are brand new project mu. i hope that’s not the case, but i’ll look into it. thanks!

[The Bogan]

Hope it is the hand brake cable or shoes then

Spin the wheels and find out

[GTSBoy]

You can check to see if the sticking is from (rear) calipers or from the handbrake fairly easily. If you pull the springs and pins out of the calipers, you should be able to (gently) lever the pads enough to push the pistons back just enough that you can move the pad up and out of the caliper. If you can create any movement at all, then that pad/piston is not the cause of the problem. If it is stuck enough that you cannot move it, then it is.

If none of the pads are the problem, then it is far more likely to be the handbrake shoes. And then you have to do more dismantling to get into those.

[itsforandres]

so, this happened again and i pulled off the wheels to take a look. the front driver’s side seems to be stuck and from what i see the lower piston(s) don’t seem to be working properly, based on the amount of dust i am seeing on that lower inner pad. does anyone have any experience with these calipers?

i am assuming that perhaps a piston is not moving smoothly as it should, but i am unable to find any information on how to take these apart to check the pistons. i am assuming the giant size 8 hex heads are the pistons, but wanted to see if anyone had any information on these. i figured i could clean them off and apply brake lube. 

anyone know the torque specs for these? any tips?

[The Bogan]

Pull the calipers for a rebuild, the full rebuild kits for Project Mu are expensive, or so says Google

You "may" be able to strip them and clean them up, but, you will probably still need new seals

Google says the pistons are steel, so probably rusty

[itsforandres]

On 11/21/2023 at 11:21 PM, The Bogan said:

Pull the calipers for a rebuild, the full rebuild kits for Project Mu are expensive, or so says Google

You "may" be able to strip them and clean them up, but, you will probably still need new seals

Google says the pistons are steel, so probably rusty

thanks! i ended up calling project mu and they recommended a shop about an hour away from me. when i took the caliper to them, they found that there was a burr in one of the pistons. they smoothed it out, put some high temp lube on all of the pistons, and now the brakes are working great.

 

thanks for pointing me in the right direction!