1990 Accord front calipers won't release

CharlesS · #1 09-03-2006, 10:19 AM

I recently purchased a 1990 Accord and after stopping at a light the front brake calipers locked. After sitting for 30 minutes they released. I have replaced the calipers,pads & rubber brake lines. Since then the calipers have not locked up to the point of stopping the vehicle as they did at first but after diving several miles the wheels are very hot and it appears the calipers are still not retracting. Has anyone had this problem and/or can give me some advice on how to solve it?

mpumas · #2 09-04-2006, 12:59 AM

The problem may be the caliper slide bolts. The caliper floats around the disc. What allows this is the mounting bolts. If they are binding, the caliper piston will retract but the caliper will not move to allow the other pad to release. So check that the caliper moves from side to side. If not remove the bolts and hone the rust out and lubricate.

jeffcoslacker · #3 09-04-2006, 09:35 AM

Quote:

Originally Posted by mpumas

The problem may be the caliper slide bolts. The caliper floats around the disc. What allows this is the mounting bolts. If they are binding, the caliper piston will retract but the caliper will not move to allow the other pad to release. So check that the caliper moves from side to side. If not remove the bolts and hone the rust out and lubricate.

Excellent advice.

Also someone here recently had a similar caliper drag and said it was some replaceable part on the caliper guides that was hanging it...I'll see if I can find it...

jeffcoslacker · #4 09-04-2006, 09:39 AM

http://www.automotiveforums.com/vbul...d.php?t=609212

Here...the metal anti-rattle/guides for the pads I assume he's talking about?

CharlesS · #5 09-04-2006, 10:00 AM

Quote:

Originally Posted by jeffcoslacker

http://www.automotiveforums.com/vbul...d.php?t=609212

Here...the metal anti-rattle/guides for the pads I assume he's talking about?

When I replaced the Calipers the new ones came with bolts & anti rattle guides. I will look again to verify one of the new guides did not get bent. Maybe I am just paranoid due to my first encounter with the Calipers locking. We drove the vehicle last night for probably 20 miles and the front rims were still very hot but there did not appear to be smoke coming from the pads as it was earlier.
Thanks for all the help !!!!!!

jeffcoslacker · #6 09-04-2006, 11:53 AM

Quote:

Originally Posted by CharlesS

When I replaced the Calipers the new ones came with bolts & anti rattle guides. I will look again to verify one of the new guides did not get bent. Maybe I am just paranoid due to my first encounter with the Calipers locking. We drove the vehicle last night for probably 20 miles and the front rims were still very hot but there did not appear to be smoke coming from the pads as it was earlier.
Thanks for all the help !!!!!!

Wheels with disc brakes do get hot in normal driving, that's not a surprise.

If you really wanna tell if you are dragging, get up on the highway, drive a few miles at speed, then coast to a stop on the shoulder, using only the emergency (rear) brake. The front wheels should be cool. If not, you found a dragger...

CharlesS · #7 11-21-2006, 08:12 AM

I thought this issue was resolved but the calipers have locked up again. The brakes are locking and you can smell the brake pads?? The only item not replaced is the master cylinder. Could this be the culprit? Thanks !

jeffcoslacker · #8 11-21-2006, 08:43 AM

Quote:

Originally Posted by CharlesS

I thought this issue was resolved but the calipers have locked up again. The brakes are locking and you can smell the brake pads?? The only item not replaced is the master cylinder. Could this be the culprit? Thanks !

Not real likely. I've never seen that happen. Anything is possible though. Master cylinders are pretty cheap, it would be nice to rule it out...

Drive it around and get them where they are bound up real good, stop and turn the wheel all the way to one side and open a bleeder screw...if it blows out a strong shot of fluid, your problem is hydraulic...if just a weak dribble or nothing, the problem is a mechanical drag.

If it seems hydrualic, you could repeat but crack the fitting for that line at the MC and see if you get a pressurized shot of fluid there, if so, it would seem the MC is creating the pressure...if not, it may be farther down the line, proportioning valve, crushed line, etc...

jeffcoslacker · #9 11-21-2006, 08:50 AM

You know, I was just thinking, I've ran across a few in the shop that appeared to be binding front brakes, because they were overheating, but after actually seeing if the brakes were binding, turned out they were fine...the REAR simply weren't doing anything (siezed wheel cylinders, etc) and the front were overworked.

You can compare how much effort it takes to roll the car in nuetral on a level surface after sitting for some time, compared to how hard it is to push after driving far enough to get the brakes cooking...this will give you an idea if they are actually binding up, or just simply overheating from being overworked (which will exhibit no dragging with the brakes released, just hot pads)

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