Locking brake problem

[Mistoffeles]

I have this recurring problem with my 94 LSI, where the right front brake is locking up completely. I've had a mechanic look at it and he can never make it happen, he has checked ABS and replaced the line. It did it before the front rotors were replaced to meet Ontario (Canada) regulations and it is still doing it after.

What happens is that sometimes when I drive for a little while and then stop for anywhere from a few minutes to an hour and then get in again to go somewhere, the brake is locked. If I go for a long drive and then park for a long time it doesn't happen.

I'm baffled, the mechanic is baffled, and I am started to get a bit ticked off that I can't enjoy my SVX properly anymore. I've had it for 2 years and never had anything seriously disabling happen to it before.

Any thoughts?

[Mistoffeles]

It's definitely a heat related problem, I just picked it up from where I left it last night and there is no problem. If I were to get custom oversized ceramic brakes and rotors in the front, this would probably solve the problem?

Cheers,

[SoCal LS-L]

The last time your brakes were done, did they inspect/lubricate the slide pins?

[SVX_MY_BABY]

Originally Posted by SoCal LS-L

The last time your brakes were done, did they inspect/lubricate the slide pins?

Ditto.

Also the rubber boot which the pin sleeve goes through can pinch. The sleeve and pins should easily move back and forth with just finger pressure. There is so much crud on the roads here in winter that most good mechanics suggest the pins be lubed every year. There are lots of poor mechanics who don't lube the pins at all when they service brakes.

You can do the lube yourself if you're mechanically inclined.

Failing that the pistons can "get lazy" and not return when the brakes are released. Usually a result of bad seals or corrosion on the piston.

The usual symptom of both conditions, plus bad lines will be to wear out the inner pads.

If lube doesn't work new caliper or seal kit may be in order as you have already done the lines.

Just a note. The only thing which causes your pads to retract from the rotor is those little rubber boots. They should be lubed inside where the pin and sleeve make contact as well as outside where they contact the caliper.

[SoCal LS-L]

Definitely, and building on that.... the next substantial drive you go on, feel the rim (DON'T TOUCH THE ROTORS!) after you stop.... if it's way hotter than the other one then you have a caliper problem, and if its been bad enough to lock your wheel up then id plan on just replacing the caliper(s) and rotor anyways.

[Mistoffeles]

Thanks, I'll have a look at those things.