Brakes Spongy! Help Me!

[SilR44]

Hi,

I've got an R33 4door completely stock standard. I recently had the front brake pads replaced with Bendix and everything worked fine for about a week.

After that the brakes were different from drive to drive ie. sometimes they'd require the lightest tap and they'd pull up, other times the brakes wouldn't work until you get to about 1/2 way down the pedal. The missus reckons at some point she went flying through a stop sign because she couldn't stop !!

At the moment, they've stopped changing from hour to hour and are left feeling really weak, like you have to get the pedal 3/4 of the way down until they start to work, then they pull up fairly well.

As far as I can see, there are no leaks, and the rotors and calipers are fine + before the new pads were put in everything was working honky dory. Any suggestions guys?

The other thing is, the r33 pads wouldn't fit my calipers, they were completely different, I found out that I have r32 calipers. Is this unusual for a '94 R33?

Cheers

Matt

[mad082]

who did the install?

did you get the rotors machined?

did you bed the new pads in properly?

it could be possible that you have a siezed piston, and it is only working sometimes. also check that a pad hasn't fallen out.

[SilR44]

A friend of mine did the install, I was there just helping out. We didn't have the rotors machined though. The pads did not require bedding in, according to the instructions. All pads are still there, none have fallen out.

cheers

[R33-Lovr]

to check if pistons are working fine, push them back with your fingers if they are too hard that might be your problem, thats what my brake specialist told me, am having big dramas with my brakes squeeling but can't figure it out

[MerlinTheHapyPig]

does the car pull to one side when braking? that will rule out a binding or stuffed piston probably.

-check for leaking brake fluid at calipers, brake lines and master cylinder

-check for kinks in the brake lines

-bleed all 4 brakes, replace the brake fluid completly if you feel the need, also check that all the lines are tight and the bleed valves are closed properly.

if it is still having problems after bleeding all 4 brakes, and the pads are installed correctly and no massive run-out on the rotors, rotors are above minimum thickness etc. then it's probably going to be a rooted master cylinder.

(also, remember to follow correct bleeding procedure especially if you have ABS brakes).

air in the lines is the usual cause of spongy brakes, did the resoviour get run dry for any reason? did you crack the bleed valve by mistake? did you loosen any of the brake lines when removing the caliper?

Edited October 24, 2006 by MerlinTheHapyPig

[JaiJai]

does the car pull to one side when braking? that will rule out a binding or stuffed piston probably.

-check for leaking brake fluid at calipers, brake lines and master cylinder

-check for kinks in the brake lines

-bleed all 4 brakes, replace the brake fluid completly if you feel the need, also check that all the lines are tight and the bleed valves are closed properly.

if it is still having problems after bleeding all 4 brakes, and the pads are installed correctly and no massive run-out on the rotors, rotors are above minimum thickness etc. then it's probably going to be a rooted master cylinder.

(also, remember to follow correct bleeding procedure especially if you have ABS brakes).

air in the lines is the usual cause of spongy brakes, did the resoviour get run dry for any reason? did you crack the bleed valve by mistake? did you loosen any of the brake lines when removing the caliper?

had the same problem and that solved it!