94 Cavalier. Problem with brakes.

wtd

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This morning my fiancée tells me that she can smell something hot and that the left side wheel was getting very hot after driving. This morning I take it for a short drive and it's not hot. I take it for a longer drive and it gets very hot. I go back home and take the wheel off and the outer brake pad is worn down to the pad depth indicator while the inner one is fine. I just put pads on this car 17,000 miles ago. I try to retract the piston with a large C clamp but no go. With the brake line hooked up, the piston would not go back down. I end up replacing both calipers since they are very cheap in price, the rotors since the one you could tell got very hot, the brake pads, and the rubber brake hoses. She has had this car for almost 80,000 miles and the calipers and brake lines had never been replaced. The left brake line had a small crack in it so I figured I would just replace them even if it wasn't leaking. I get everything back together and while it doesn't get screaming hot like it was, it is still getting warm on that side when the passenger side is cool to the touch. After the car sat for a little while, the caliper was pretty hot and so was the rotor so something is still not right. The car brakes straight. I've been doing brakes for years and while I have experienced a stuck caliper on a previous vehicle, after I replaced the caliper and hose, I didn't have any more problems. So what else should I be looking at that could be causing this slight pad drag? Thanks for any ideas or suggestions.
 
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If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little. One pad wearing more than the other means the slide pins are sticking but since you replaced everything that has probably been resolved.
 
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I would start by manually compressing the caliper slightly. Check for any sticking or binding of the caliper on the guide pins. With a brand new caliper and guide pins, it should move easily.
 
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Originally Posted by mk378
If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little.
Good test. 25 year old brake hoses? Make fun of me if you like, but I've had brake hoses swell shut when they got that old, like arteriosclerosis, then the pistons couldn't retract. Same symptoms.
 
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Originally Posted by mk378
If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little.
I had this problem with my mercedes w123. Notably, the brake pedal had zero play, felt like stepping on a block of wood. Your muscle memory will notice that something's off.
 

wtd

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Originally Posted by mk378
If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little. One pad wearing more than the other means the slide pins are sticking but since you replaced everything that has probably been resolved.
If the brake light switch needed adjustment, wouldn't both sides be dragging?
 

wtd

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Originally Posted by eyeofthetiger
I would start by manually compressing the caliper slightly. Check for any sticking or binding of the caliper on the guide pins. With a brand new caliper and guide pins, it should move easily.
The new guide pins were moving smoothly. After I had gotten everything bolted on except for the wheels, I tried moving the rotors on both sides. The driver's side did drag more than the passenger side. I thought that everything would work itself out after taking it on a test drive. I will try manually compressing the calipers and see what happens. Probably won't happen tomorrow since it's supposed to snow and be cold.
 

wtd

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Originally Posted by MrMoody
Originally Posted by mk378
If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little.
Good test. 25 year old brake hoses? Make fun of me if you like, but I've had brake hoses swell shut when they got that old, like arteriosclerosis, then the pistons couldn't retract. Same symptoms.
Both front rubber brake hoses were replaced with new ones so I don't think it's that.
 

wtd

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Originally Posted by eljefino
Originally Posted by mk378
If the master cylinder piston doesn't come all the way back when no one is pressing the brake pedal, pressure can build up and cause drag. Check if there is pressure build up when the system is warm after a drive by putting the clamp on and try to retract, then crack open the bleeder to see if that relieves it. This could be a simple as adjusting the brake light switch back a little.
I had this problem with my mercedes w123. Notably, the brake pedal had zero play, felt like stepping on a block of wood. Your muscle memory will notice that something's off.
The brake pedal does have play In it so it's not like stepping on a block of wood. It feels normal to me.
 
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Originally Posted by wtd
Both front rubber brake hoses were replaced with new ones so I don't think it's that.
Ah, should have read more carefully.
 

wtd

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Originally Posted by OILJUNKIE
I think you misunderstood your fiancee she said,"you were hot"
LOL. That is definitely not what she said. I sprained my ankle after putting tools up in the shed to finish off this day and she barely acknowledged that. Granted she just go off work from working overtime but after working on her car all day, you would think she would be more appreciative.
 

wtd

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I finally did try manually pushing the piston back in and it went in fine without having to crack open the bleeder valve. I rechecked and the caliper slides fine. She drove it into town the other day and while the wheel did not get hot, you could smell the brake material when she got back. At this point all I can figure out is that something could be wrong with the master cylinder that is not allowing the pads to retract all the way.
 
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That is possible^^^ and what others said make sure the pedal is coming all the way back when you release the brakes. I had this issue with an old S-10 V-8 swap that someone switched it from power to manual brakes. It drove me nuts trying to figure it out as I have never heard of this before. Lesson for me learned not to work on someone else's cobbled up job.
 

wtd

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Originally Posted by Silverado12
That is possible^^^ and what others said make sure the pedal is coming all the way back when you release the brakes. I had this issue with an old S-10 V-8 swap that someone switched it from power to manual brakes. It drove me nuts trying to figure it out as I have never heard of this before. Lesson for me learned not to work on someone else's cobbled up job.
The pedal is coming back up because I adjusted the brake switch like it said in the service manual and I pulled the pedal up until the brake switch quit clicking. It wouldn't go up any farther anyway.
 
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I'm thinking master cylinder - GM uses that weird quick-take up MC I had to deal with on a 2dr Tahoe(C/K Blazer). Unless that Cavalier has ABS too. Where are you buying calipers from? AFAIK, the Americans didn't use floating calipers like the Japanese did that use slide pins in a bolted-on bracket. They used a similar concept but those calipers slid on slide pins that threaded into the steering knuckle within rubber sleeves. I recall having to go through 2 calipers when I did brakes on that Tahoe.
 
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wtd

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This Cavalier does have front ABS and has a large contraption bolted to the MC for the ABS system. I got the calipers from O'reilly's. This setup is two pins that bolt onto the steering knuckle that go through rubber sleeves on the caliper itself. The problem seems to have worked itself out. The wheel is not getting hot and I've not smelled any brake material lately. I will keep an eye on it for now.
 
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