Rep Power: 0

Hello,

So I have been having some brake issues. My rear wheels, specifically it was mostly right rear wheel would lock up under slightly-moderate braking. I replaced the rear drum cylinder, rear shoes, shoe springs, and it continued. My mechanic was puzzled so only replaced rotors and pads in the front.

I eventually replaced the proportioning valve, and its significantly better. I get good braking, but I notice particularly in rain, my front left wheel locks up much earlier than I would expect it to. The right wheel remains unlocked and kind of is half good in that you can steer and continue to brake, while the left locks up and slightly slides the front of the car to the right.

Does anybody have any experience with this. I have re-bled my brakes at least 3 times. I'm confident there isn't air. I'm at the stage of thinking the master cylinder is causing something.

My civic's proportioning valve has two lines going to the MC and four to the wheels. If that helps describe which type of braking system I've got.

By the way neither front caliper is seized. Rear cylinders are new.

Thanks.

 
Rep Power: 0

If everything is working fine up to the master cylinder then that is probably it.

 
Rep Power: 149

Just reading what has been done up to this point and what has not points to a tight (probably rusted behind seal ring..not stuck but tite) caliper. (one caliper is stronger then other) what is still confusing is the pull you call out. Usually in my experience, what locks is the strong good one and the the direction it yanks. Obvious, you do not have ABS and an very old 90% rebuilt system. 50 years has shown me (the hard way) that once you wear out the first OEM pads, you can (maybe get one one more service life out of it with new pads or shoes. After that, if you keep the car, you need to bite the bullet and replace it all. Problem is, when you go aftermarket, and rebuilt calipers , hardware and such, most is junk. Then of course, like me piecemeal it. If you're proportional valve was bad, bet you have a lot of junk floating around in system. If it was me, I would pull both calipers off. Push the pistons back in and have someone press the brake pedal very easy with motor off and power bled off master cylinder by braking before you pull calipers. Takes 3 people. See if both pistons move about the same with just a light short movement. The one that does not, go ahead and push the piston out by wedging the other. Rebuild it and then do the other or just get two new calipers. I rebuild mine if they are not rusted. That way I know what I have and I cannot or will not pay the dealer price for a caliper and will not buy aftermarket junk anymore.

 
Rep Power: 367

or even a clogge line could be the culprit.

 
Rep Power: 518

Contaminated linings?