trackrabbit21

Checked all the calipers, even repaired the front ones, all the pistons were dirty but no pitting, cleaned them up and they were smooth. Replaced the rubber boots and such as well. Also replaced all the brake lines w/ SS lines, and gravity bled the entire system, from FR going counter clockwise.

Still getting some brake drag, so my question is, would the brake master cylinder possibly be sticking when I depress the brake pedal, or could it be that I'm putting too much brake fluid into the system making the brakes overwork?. Filled it up to the max, and also checked for leaks as well. No leaks under the dash or on the brake booster.

I'm getting too much pressure from somewhere...and last thing I need to replace is the master cylinder and or brake booster, just looking for some insight and maybe even able to help anyone with the same issue.

trackrabbit21

bump

Update - when I turn the car on for the first time and depress the brakes a few times and try to roll the car with minimal effort it doesn't budge but when I turn it off, the brakes suddenly free up. Could it be the brake booster?

cdelena

Doubt a MC will cause dragging but a dirty/bent/rotated caliper pin is a common cause.

trackrabbit21

greased up the pins with the High temp urea grease, all four sides so I dont think that would be the issue

S2KIrishman

i had a sticky master cylinder on one of my old civics that caused the brakes to lock when they got hot...never had any issues with the S with it though...so id say yea, its possible

GvilleBrink

Did you fix this issue? im in the same boat as you and i have replaced or looked over everything i could possibly think of besides changing the master cylinder, brake booster, or proportion valve

Billman250

There is a procedure for checking stuck brakes...

Car on stands, have someone hold the brake pedal. Apply rotational force to each wheel by hand (it will be locked) then ask the assistant to release the brake pedal. Each wheel should immediately become free.

If you find a wheel that is not releasing, or releasing late, pull the wheel off.

Have an assistant hold the brake and release and make the wheel stick again. While its stuck, OPEN the bleeder. If the wheel does not free up instantly, then you have a caliper or slider sticking.

If the wheel frees up when you open the bleeder, then you have a defective brake hose, or another type of hydraulic restriction.

A poorly adjusted master cylinder would hold the brakes on, but I doubt you would find that from a factory original installed MC.

ericss2kturbod

I had same problem i had replaced front calipers but had air in system i drained all fuid and to bleed them all around i literally took like thirty mins bleeding systme till fuid came out clear and no air after was workin good till now they still good

matthewLC

Sorry to bump such an old thread but was there ever a solution? I'm having the same problem with my rear brakes. Just bought my ap1 and the brakes were toast.

So I replaced Pads and rotors all around. Then replaced the rear calipers and brake hoses the whole way around. Brakes a still not fully releasing. The only thing left is the master cylinder. I just don't want to keep throwing parts at it hoping it's going to fix my issue.

And by not fulling releasing they're just barely dragging. I can still turn the wheels by hand but they drag slightly. Pads and rotors are oem Honda.