Brake problem

[Ignas]

Hi,

I have a problem with my 1985 R 4's brakes. The car has brake shoes (front and rear). When i push brake pedal down, rear right shoe stuck. It seems that fluid going in one direction, and can't return to master cylinder. Only way to loose tension on a wheel is unscrew the air bolt from wheel piston and let the fluid come out from there. All parts (wheel pistons, master cylinder, brake lines and hoses are quite new) also there is brake limiting valve. Is there any ideas how to find out where is a problem?

Sorry for my english

 

[pepper]

There is a brake valve, on the left hand side of the chassis, just in front of the rear suspension mount.

The other thing to look at is perhaps a collapsed hose, even though it is new.

No excuses needed for your English, it is very good!

 

[Ignas]

Thanks, I'll check these today, it strange, cause in other direction (from master cylinder) fluid runs easily.

 

[malcolm]

It's worth checking the brake pipes have been connected in the correct place to the proportioning valve - the two outlets are at the same level and the inlet slightly higher.

Otherwise it does sound like a collapsed brake hose. There isn't much else that would allow one side to work and the other to build pressure.

 

[Ignas]

Ok. So, connections from left to right: 1. Rear left
2. Rear right
3. Inlet
1 and 3 Are a little bit higher, than 2

 

[malcolm]

It's connected the wrong way. Should be:

1. Rear Left
2. Inlet
3. Rear Right

The two outlets should be the same level and the inlet lower (not higher as I said earlier). That would explain the problem with the rear right brake.

 

[Ignas]

Thanks a lot malcom! I have just changed connections. The back was lifted so at first i was not able to get any fluid running from master cylinder, to the right rear, but it seems to be all good when the car sits on wheels. So brake limiting valve is working, but why just on one side of the car?

 

[malcolm]

Fluid doesn't run well through a hole on full restrict when you have air in the system? So long as the rear brakes satisfy your vehicle test and don't lock up under braking I should imagine they will be working OK.

 

[pepper]

Yay. nearly fixed!

I try and bleed the rears with the vehicles wheels on the ground, but I'm lucky I have a ramp.

 

[Ignas]

Sorry, for late answer, i was a little out of my garage things, but it seems to be ok now with my brakes, thanks again!