Oldsmobile/Buick Repair: Front brake caliper disassembly, front brake caliper, caliper piston


Question
Hi,

This is actually a general question about front brakes. The vehicle is a '87 Toyota 2WD truck (the only Toyota guy here is maxed out). I'm getting intermittent drag on my right front brake. I believe that I ruled out a problem in the brake line or above by opening the bleed valve at the caliper, which doesn't affect the drag (if pressure in the line were high due to anything, this would relieve the pressure). I believe that the caliper piston (the caliper is the type that slides on 2 pins and has a single piston) might be sticking. I have not worked on front brakes before, so it is unfamiliar to me. I have removed the brake line and the caliper is free of the vehicle. My Haynes book tells me to remove the rubber boot retaining ring and then the rubber boot surrounding the piston before I remove the piston; however, I see no retaining ring, and it appears that the boot extends all the way down into the piston bore. (I don't expect you to be familiar with this particular caliper, but want to mention this in case you have any helpful comment on it.) Since I can't see how I can remove the boot, the next step is to remove the piston. I don't have compressed air. I connected a bicycle air pump to the brake line input (it made a good seal) and pumped up to 140 pounds pressure (pump has a gauge on it), but the piston didn't budge. Compressed air usually isn't compressed nearly that high in my experience, so I don't know that that would do the trick. Do you have any suggestion? How about if I reconnected the brake line and depressed the brake? Is than an acceptable method to get the piston out? (I know to put a piece of wood between the piston and caliper since the piston can come out forcefully and get damaged.)

Thank you in advance,
Scott

Answer
HI SCOTT..WELL SCOTT YOU ANSWERED YOUR OWN QUESTION  YES HOOK UP THE LINE AND BLOCK AND PUMP IT UP IT WILL COME OUT .BUT IF YOU ARE HAVEING THIS KIND OF TROUBLE .THE CALIPER IS NOT ANY GOOD ANYWAY.AND 5 PSI OF PRESSURE SHOULD BE SUFFICIENT.SO BE REAL CAREFUL..YOU WILL MORE THEN LIKELY HAVE TO REPLACE THE CALIPERS BUT MAYBE YOU WILL BE LUCKY.GOOD LUCK PLEASE TAKE A MIN TO RATE MY SERVICE TY BILLYMAC