right front brake locking up

[mounddog]

Ive almost got all my buick problems fixed (except for the RPM drop while accelerating), and Now the right front brake is locking up after driving for a few miles. Ive changed out calipers twice now, and had rotors turned. Brakes bled, and there master cylinder is full. Brake pedal feels fine. After i drive for about 5 miles, and stop car, and then start again and continue - i start feeling the car dragging, sluggish - and then smell the Nasty brake pad burning smell. Its the right front caliper locking up. Two new sets on it - and no go - any suggestions? '92 park avenue, 111k

[pcv]

Replace the flex line to the caliper. Probably broken inside due to years of crimping when doing brakes by techs.

[creslevi]

you might check to see if the line to the caliper has a twist in it, also follow the steel line the flex line hooks up to and lock for kinks or dents, which could restict the flow of fluid from releasing when you take your foot off the brake, when applying the brakes you have the hydraulic pressure (your foot and the power brake booster)Nothing there to make it release, except release of the pressure you apply when braking, I had a line dented going across an axle once (probly from a rock kicking up from the road) and it would'nt release right, Also you probly know any slight brake fluid on th pads will make it grab. hope this helps
Rick

[mounddog]

Looks like my old brake line must have had a kink or some such as suggested - after replacing it i dont seem to have the locking up caliper problem anymore (knock on wood big time). Thanks for the suggestions - Mike