Sticking Front Brakes

Sometimes a sticking caliper piston can be determined when compressing the pistons during a pad installation.

This may come across as a piston that seems to be difficult to compress into the caliper bore. At 12 years of age, hardened caliper piston seals is a possibility.

Took the civic for a good test ride and after 10 miles, the brakes started dragging. Got out with the infrared thermometer and both sides were reading the same about 640 deg. measured right on the caliper on each side. They dropped to about 250 after a couple minutes. I purged the bleeder on both sides and was able to continue back.

With the temp being the same on both sides, I’m assuming that both calipers are dragging with the master cylinder being the common point to both sides. Is it possible that both brake hoses are bad at the same time? Is this common?

You need to find a brake specialist with a good reputation. The master cylinder is not the common point to the two front brakes, there is no common point unless you consider the brake booster, and that would also affect the rear brakes.

The brake system is an X feed type, meaning that there are two cylinders in the master cylinder, each one feeds one front brake and the opposite side rear brake.

It would be odd for both front brakes to have the same problem at the same time. Do you have ABS and if so, have you tried unplugging the ABS module and test driving the car to see if the brakes start dragging? I don’t really think it is the ABS, but it wouldn’t hurt to try this test anyway. Its the only other common point besides the booster.

Yes, both hoses can have this issue, it just doesn’t seem like it would happen at the same time unless the brake fluid got contaminated some time in the past.

Have you done a complete flush of the brake system?

Went through the entire brake system. Found the adjusters on the rears frozen due to rust. Looks like the rears wore out (metal on metal) the somebody put new shoes on and left the scored drums on. Replaced the adjusters and put new drums on…All good on the rear.

Replaced both brake hoses and put new pads with new clips on the fronts. Lubed up the slide pins and completely flushed all the fluid. Took for a test drive and it’s still dragging. Had to open the bleeder to get the vehicle back.

The caliper pistons retracted easily while changing the pads but I guess one of them is dragging.

Sounds like you’re due for a caliper.

Even if the slides are free, if the rubber “square cut ‘O’ Riing” (I don;t know what Honda calls theirs) that distends when you press the brakes and then slightly retracts the pads when you release the pressure is tired (they are, after all elastomers), than you need a new caliper…or to rebuild the old one if you’re up to it.

Just one thing to check if brake work has been done before is to make sure the hose itself is not twisted and the lines on the hose are straight. If the caliper has been pulled off before it is possible that they got twisted when put back on which could cause some constriction. Otherwise might be a good idea just to replace the hoses while you are replacing the calipers just to be done with it.

Replaced both front calipers, pads, rotors, both brake hoses, lubed the pins up, and completely flushed the brake fluid. They are STILL sticking. I didn’t want to throw parts at it but looks like that is what is happening. What’s left? The master cylinder is the only thing left as far as I know. Would the master cylinder cause this?

Is there an ABS light lit. The control module could be keeping pressure on the calipers. You could pull the ABS fuse and check to see if they are still dragging. I would not think the master cylinder would cause this, but the booster may be holding pressure on it and not releasing.

Testing and Inspection

Brake Booster Test
Functional Test

With the engine stopped, press the brake pedal several times to deplete the vacuum reservoir, then press the pedal hard and hold it for15 seconds . If the pedal sinks, either the master cylinder is bypassing internally, or the brake system (master cylinder, lines, modulator, proportioning valve, calipers, or wheel cylinders) is leaking.
Start the engine with the brake pedal pressed. If the pedal sinks slightly, the vacuum booster is operating normally. If the pedal height does not vary, the booster or check valve is faulty.
With the engine running, press the brake pedal lightly. If the brake pedal sinks more than 10 mm (3/8 inch) in 3 minutes , the master cylinder is faulty. A slight change in pedal height when the A/C compressor cycles on and off is normal. (The A/C compressor load changes the vacuum available to the booster.) Leak Test
Press the brake pedal with the engine running, then stop the engine. If the pedal height does not vary while pressed for30 seconds , the vacuum booster is OK. If the pedal rises, the booster is faulty.
Turn the engine off and wait 30 seconds . Press the brake pedal several times using normal pressure. When the pedal is first pressed, it should be low. On consecutive applications, the pedal height should gradually rise. If the pedal position does not vary, check the booster check valve.

Disconnect the brake booster vacuum hose (check valve built-in) (A) at the booster (B) side.
Start the engine, and let it idle. There should be vacuum available. If no vacuum is available, the check valve is not working properly. Replace the brake booster vacuum hose and check valve, and retest.
Start the engine, and then pinch the brake booster vacuum hose between the check valve and the booster.
Turn the engine off and wait 30 seconds . Press the brake pedal several times using normal pressure. When the pedal is first pressed, it should be low. On consecutive applications, the pedal height should gradually rise.
If the pedal position does not vary, replace the brake booster.
If the pedal position varies, replace the brake booster vacuum hose/check valve assembly.

Does not have ABS…Civic LX

If it is the master cylinder, then the rear brakes must also be dragging or there is something blocking the passageways in the distribution block, but again this is an X brake system, so something that is causing a problem on one front wheel should also affect the opposite rear wheel.

Everything on the rears are operating properly. This is affecting the two fronts. When they start to drag after a 4 or 5 mile ride, I pop the bleeder on the front caliper to release the hydraulic pressure and I can continue driving down the road. The old rotors turned blue from the extreme heat they were getting. I’m trying not to “cook”" the new rotors.

Brake Proportioning/Combination Valve is sticking.

@knfenimore I was just reading that page, so front brakes could be dragging, but not the back brakes, maybe the range of pedal motion is restricted.

Before replacing the master cylinder make sure that there is some free play between the master cylinder plunger and the brake pedal/booster push rod.

I believe I found the issue with the dragging brakes…In the process of working on the car, (timimg belt, tensioner, spring, cam & crank seal, water pump, t-stat, rad. cap, upper & lower rad. hose, flush coolant, plugs, pcv valve, both drive belts, 2x tranny fluid change, etc.) I noticed the brake lights were on with nobody in the vehicle. Upon inspection, found the plug on the pedal that actually hits the brake light switch was missing.
I put a screw with a big head in the hole on the brake pedal and when I put the switch back into the receptacle, I just shoved it in with no regard to the positioning of the pedal itself. The switch was keeping the pedal from retracting fully causing all this headache. I put a stove- bolt type bolt in the hole with a nut to keep from falling back out then made sure it was as far retracted back as I could get and put the switch on.

After a good 30 to 40 mile ride, the brakes worked properly. It was actually a good thing this happened because it made me go through the whole brake sysytem where I found and fixed several things that needed to be done anyway. The car is going to a new 16 year old driver so at least I know the brakes are good for the safety of this novice driver.

Well that’s one for the books. Guess start with the obvious first.

Thanks for the update, glad the problem is resolved.

I fought with sticky front brakes for a long time. Finally dawned on me that I had changed the master cylinder and the rod was probably a bit to long. Went to the auto parts and bought a thick muffler gasket, installed behind the master cylinder; no more sticky front brakes. Gas mileage shot through the roof!
Hope this helps someone.

This 3 year old thread has been solved and it had nothing to do with the rod.

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If the MC rod isn’t the correct length usually a shop would just replace the MC using one with the correct length rod. In any event part of dong a MC job is checking all the parts dimensions of the new part match with the part you are removing first But if the “Muhammad won’t go to the mountain, so bring the mountain to Muhammad!” method worked for @bambklr , then it worked!! MacGyver solution.