Left front Brake, braking, almost locking up, when no braking is applied.

thepickupplace

Hello, needing some assistance with troubleshooting. I have a 1990 Buick Lesabre Custom with the J41 brake system on it. Right after I bought it the left front brake caliper seemed to lock up. It was like it was applying the brakes constantly when no braking was applied. I replaced the caliper as it seems locked up when I removed it. Worked good for a couple weeks and now it is doing it again. It appears to be just the left from braking all the time. It gets hot and smokes... I have researched the issue and there appears to be a lot of issues with the ABS system that is on a lot of the Buicks. However, from what I can tell mine has the J41 system on it. much simpler. Any input to what the problem may be or advice would be appreciated before I start changing parts? Thanks, Tom

imidazol97

Does the J41 mean it does NOT have ABS?

I've heard radio mechanics get this kind of call from a person with a problem car. Since you're replaced the caliper, and I assume the slide bolts and rubber grommets, that eliminates the caliper not sliding back.

Another problem with age is that inside of the brake hose from the caliper to the metal line detriorates and the interior won't let fluid back out of the caliper after the high pressure applies the piston. I believe, I believe, the test was to wait until the thing tightens up, then open the bleed screw. If the fluid comes out under high pressure, that means the fluid is not returning to the master cylinder after pressure is release in the line. The pressure being held in the caliper is applying the brake just as though your foot is on the pedal. A fairly cheap fix to just buy a new hose section and a couple of copper seal washers to replace that if you find it's the problem.

Of course, I believe a problem in the ABS could do the same thing.

Good luck.

thepickupplace

Thanks, the diagram I am looking at that matches my Buick is the J41 system and it does not appear to be an ABS. However, saying this, I thought most 1990's and newer models had some kind of ABS system. Still working on that one. I will try the suggestions you made and see what happens. Many thanks, Tom

thepickupplace

imidazol97, thanks again. It was the brake line to the caliper. I took it off and couldn't even blow through it. Works great with the new line... have a great day.... thepickupplace...