Disassembly and Assembly

DISASSEMBLY
1. Drain old brake fluid out of caliper into drain pan.

Figure 15:

2. Remove piston dust boot. Use screwdriver to push boot out of groove.

Figure 16:

3. Pad outboard shoe side of caliper interior with a minimum 1 inch thickness of shop towels. Towels will prevent piston damage when piston comes out of the caliper bore.
4. Remove caliper piston with short bursts of compressed air. Apply air pressure through fluid inlet port of caliper.

CAUTION: Do not blow the piston out of the bore with sustained air pressure. This could result in a cracked piston. Use only enough air pressure to ease the piston out.

WARNING: NEVER ATTEMPT TO CATCH THE PISTON AS IT LEAVES THE BORE. THIS MAY RESULT IN PERSONAL INJURY.

Caliper Piston Seal:

5. Remove caliper piston seal with wood pencil or plastic tool. Do not use metal tools as they will scratch piston bore.
6. Remove caliper slide pin bushings and boots.
7. Remove caliper bleed screw and cap.

CLEANING
Clean the caliper components with clean brake fluid or brake clean only. Wipe the caliper and piston dry with lint free towels or use low pressure compressed air.

CAUTION: Do not use gasoline, kerosene, paint thinner, or similar solvents. These products may leave a residue that could damage the piston and seal.

INSPECTION
The piston is made from a phenolic resin (plastic material) and should be smooth and clean.
The piston must be replaced if cracked or scored. Do not attempt to restore a scored piston surface by sanding or polishing.

CAUTION: If the caliper piston is replaced, install the same type of piston in the caliper. Never interchange phenolic resin and steel caliper pistons. The pistons, seals, seal grooves, caliper bore and piston tolerances are different.

Fig 14 Honing Piston Bore:

The bore can be lightly polished with a brake hone to remove very minor surface imperfections. The caliper should be replaced if the bore is severely corroded, rusted, scored, or if polishing would increase bore diameter more than 0.025 mm (0.001 inch).

ASSEMBLY

CAUTION: Dirt, oil, and solvents can damage caliper seals. Insure assembly area is clean and dry.

1. Lubricate caliper piston bore, new piston seal and piston with clean brake fluid.
2. Lubricate caliper bushings and interior of bushing boots with silicone grease.

Bushings And Boots Installation:

3. Install bushing boots in caliper, then insert bushing into boot and push bushing into place.

Seal Installation:

4. Install new piston seal into seal groove with finger.

Piston And Dust Boot:

5. Install new dust boot on caliper piston and seat boot in piston groove.

Caliper Piston Installation:

6. Press piston into caliper bore by hand, use a turn and push motion to work piston into seal.
7. Press caliper piston to bottom of bore.

Piston Dust Boot Installation:

8. Seat dust boot in caliper with Installer Tool C-4842 and Tool Handle C-4171.
9. Replace caliper bleed screw if removed.