Brake Binding - Sticking Rear Brakes

[DRTDVL 4 1 Cars]

Good morning everyone...

 

The 205's current got a front rear split on the racecar and i'm getting a bit of brake binding once the hydrolic handbrake has been used. It's like the m/c for the handbrake is filling back up very slowly from the brake side of things.

 

The way it's been setup from what i can see (please note i didn't install or have installed the handbrake), there is a 4 port front m/c that has two splits for the front brakes one for each brake. Then there is a single line running to the handbrake m/c then one line out of the m/c which then splits into two for the rear brakes. The 4th port has been blocked off.

 

I'm just wondering if anyone has run into this problem before and how they fixed it? As i think the binding has caused the rear pads to over heat and crumble.

[welshpug 1,658]

sounds like the rod from the lever to the mc needs adjusting a little, travel of the lever will increase a little.

[DRTDVL 4 1 Cars]

Which one?

 

the handbrake or the pedal?

[taylorspug 7]

The pedal, I had exactly the ssame thing on my car, rear brakes binding, adjusted the rod from the pedal inside the servo and the problem was cured.

[DRTDVL 4 1 Cars]

Is that with a hydro handbrake?

[welshpug 1,658]

no, the handbrake, as it only happens to the rears.

Edited February 4, 2009 by welshpug

[taylorspug 7]

Happens if the rod in the servo is too long aswell, it only binds the rear brakes on. Ive no experience of hydraulic handbrakes in 205s, only going off problems ive encountered on normal brake setups.

 

If you want to quickly see if its the handbrake or the servo rod, try disconnecting the linkage from the handbrake so that the master cylinders can return fully, then go for a bit of a drive.

[DRTDVL 4 1 Cars]

Been chatting with my mechanic.

 

He thinka that the master cyclinder that was used might be for a car with drum brakes and has a foot locker in it... supposably it keeps some pressure in the line so that the drums don't need to be pumped or something...

[Rob Thomson 6]

It's a common problem with hydraulic handbrakes.

 

Some master cylinders are better than others for the role of hydraulic handbrakes. The cheap ones that come with the kits often cause problems if you over-lap braking with the foot-brake and handbrake, resulting in the rears locking on to some degree.

 

My trusty old 106 Rallye rally car had an AP Racing cylinder that was designed for the purpose and worked perfectly. One of my mates resolved the problem in his rally car (with Girling cylinder) by cutting a small nick into the handbrake master cylinder's piston seal, to allow the fluid to bleed back. Obviously that means you can't hold the handbrake on either, but that's normally not a problem as you just give it a quick tug anyway.

[Rippthrough 98]

Quite often they don't come back properly to uncover enough of the port to supply line, at best you might cure it with a better return spring, at worst you might have to strip the master cylinder and reshim the internals.