Nikedecades

Really trying to get the brakes up to speed on my 79. Did the rotors, shoes, pads, all new brake fluid through all the lines. Went around and tried to some more aggressive braking to test it out. Was going well, brought it up to speed around 80km/h and did some more hard brake testing which also went relatively well. Now the brakes are sticking which they weren't before, it sticks somewhat intermittently when I am slowing down coming up to a light or a stop sign, I almost have to flutter the brake pedal to get it to release.

Questions:

1. Does this have to do with the front calipers and the cylinders? or with the brake master assembly? or with the brake pedal?
2. What do I have to do to the brake system to make it feel more modern? Currently it feels as though a modern car is able to stop 2x faster than this car, which will be bad news for me if that day ever happens.

Thanks in advance!

rxtasy3

iTrader: (2)

today's cars with 4 wheel disk and ABS, u will never get that 79 to brake anywhere near modern. check calipers again. make sure they're not binding up. the front calipers "float", meaning they're able to slide side to side. always make sure to lightly grease the pins. otherwise the caliper may hang up keeping pressure on the outer pad. with new rotors, pads, etc, there is a "bed-in" procedure that u will need to do.

impulsive-rx7

iTrader: (2)

Did you rebuild the calipers? If not you may need to. Any corrosion sitting in the caliper piston bore will cause the caliper to stick or not release.
I just went through this with mine.

impulsive-rx7

iTrader: (2)

Also, you can feel your wheels after a drive... The wheel with the sticking caliper will be noticeably warmer than the others. It might be hot if it's bad, so don't burn your hand!

mazdaverx713b

iTrader: (91)

When you replaced the front brakes did you service the caliper brackets and pin? The rust and old brake dust should be cleaned from the bridges and the fitting kit for the pads should be clean as well. A light amount of grease can be applied on the bridges before the fitting kit goes back on the bracket and then a light amount of grease can be applied to the pad contact point on the fitting kit. This will assist the pads in being able to move freely off of the rotor when not in use.

mid you make sure to use the spring for the pads? This will also help the pads return to rest when not in use.

The front calipers, if original, may need rebuilt or replaced. If its Pulling one way or the other and heating up, you have something binding. Were the caliper pistons easy to compress? Does the car pull when the brakes are not being applied?

Nikedecades

Thanks,

I will try this tonight and update.

mazdaverx713b

iTrader: (91)

Keep us updated on what you find out!

Nikedecades

Alright, I had done as you had suggested and it seems to have gotten me half way there. But I am still finding the brakes sticking intermittently/randomly when easing up to a light or a stop sign, then they'll release.

I was looking around and found some people commenting on swollen brake lines? Not sure if any of you have heard of this or had experience with this?

How do I trouble shoot if its the caliper cylinder rubber has ripped or not without taking it apart? I was inspecting them but a little difficult to tell whats going on when its all folded up in there.

j9fd3s

iTrader: (3)

the swollen brake hoses tend to be a German car thing, the hose will look ok from the outside, but it deteriorates on the inside and will act like a check valve. if you cut it open it looks like someone with a clogged artery.

on the race car i like to spin the wheel when we put it in the air, and we have found a lot of calipers that are sticky. on the Rx7 there is the piston that needs to retract (just a little) and then a caliper slide

GSLSEforme

Rebuild calipers and replace brake hoses.
Now a good time to upgrade to stainless braided brake hose for better pedal feel.