If the pistons won’t come out by hand, compressed air forced into the fluid holes can be used to free them. If they are stuck, tap them with a soft wood block, making sure not to hit directly on the grooves. A word of caution here-around the piston and in the caliper are grooves that hold the dust cap in place. These grooves are very fragile, don’t break or bend them.
Take the caliper to the workbench and remove the bridge pipe or balance tube from the caliper. Use a 5/8″ wrench to remove the flexible brake line from the caliper. Now, take out the two 1/2″ bolts that hold the caliper onto the spindle. Next, remove the linings by twisting them up and out of the caliper. (It’s important to be very careful and not damage the brake rotor-Ed.) With a screwdriver or other prybar, pry the linings away from the rotor. But, if it does leak, here’s a remedy: First, remove the two 1/4″ bolts and retainers that hold in the linings. The first rule of brake calipers is: If it works and doesn’t leak, leave it alone. Now you see the caliper in all its leaky glory. First, jack up the car and remove the tire. Okay, time to rebuild the front calipers. All my brake fluid ran out the left caliper onto the floor. A quick look on the floor told me where my problem was. A quick look in the fluid reservoir showed I had a problem. I pushed on my brake pedal, and not only did my car not stop, the pedal went all the way to the floor. I found out it was time to rebuild mine when I was backing out of the garage one day. How do you know when it’s time to rebuild your front calipers? Split-bodied calipers (2 halves bolted together) should not be separated -Ed.) (While this article applies specifically to the early “solid-bodied” calipers, dealing with the later “split-bodied” calipers follows the same principles.