Went to change the pads and rotors on front of my car today and discovered something I’d never seen before. When I pulled the driver’s side wheel, the pads were worn down almost completely and had gouged the rotor slightly. That’s pretty much what I expected. Compressed the piston back and installed the new rotors and pads. Pulled the passenger side wheel off and the pads and rotors were almost new looking. What happened? The caliper on the other side couldn’t have seized or I wouldn’t have been able to compress the piston, and the other caliper has to be working or the car would pull to one side when I hit the brakes (which it doesn’t). Any ideas? The car’s a 1984 Honda Accord.
Obviously you got the car used. Were the brakes changed in pairs before you bought the car? If not, there’s your answer.
It could also be an alignment or installation problem, or even a sticking caliper. Could be anything.
The drivers side pistons are sticking, they don’t move back away from the discs when you take your foot off the brake pedal, alternatively there is the possibility if the brake or mechanism is designed to float that it has stuck on its spigots.
Either way, you need to take out the pads on that side, pump out the pistons a little and clean them, since they are usually phospor-bronze they won’t be corroded but there will be a build up of old brake pad dust which has itself corroded onto the piston (mainly 'cause the pad will be sintered). You can buy brake cleaner fluids or you could just use metal polish like Brasso which I find cheaper and more effective.
If the caliper is designed to float and has stuck then you will need to find a way of removing it and cleaning the spigot and the locating hole on the caliper, I’m not familiar with the way this car is made but it could mean taking the wheel off to get at things and possibly taking off the brake lines.
If things are like this on one side then its a fair bet they are headed in the same direction on the other side, so its worth cleaing those pistons up while everything is moving ok and so still pretty easy to do.
Your self adjusting brake mechanism is broken.
Hmmm. Sounds like the easiest thing for me to do (though not necessarily the cheapest) is simply to replace the calipers. I’ve rebuilt 'em before and its not much fun. Would have bought replacement calipers when I got the pads and rotors, but I’m a little short of cash at the moment. Thanks, guys.
No, don’t give up yet. Look at what casdave said, and just check and make sure that the caliper assembly and pistons can move freely. Sometimes this is a matter of just exercising them and cleaning them, without having to rebuild. You have little to lose in trying that out first - just make sure all the parts are clean, rust-free, and well-lubricated.