BUCKET AS-EXCAVATION 1682706 - Caterpillar

Inspect Brake Disc
Illustration 1 g00783625
Typical section through disc (A) Minimum disc thickness (B) Maximum disc wear on each side (C) Original disc thickness
Table 1
Lining and Backing Plate Thickness    Maximum Disc Wear (Each Side) (B)    Minimum Disc Thickness (A)    
7.1 mm (0.28 inch)    
1.5 mm (0.06 inch)    
12.7 mm (0.50 inch)    
8.6 mm (0.34 inch)    
2.3 mm (0.09 inch)    
11.2 mm (0.44 inch)    Original disc thickness (C) is 15.875 mm (0.6250 inch). If the disc is worn beyond the wear limits, replace the disc.Inspect Linings and End Plates
Illustration 2 g00783016
Cross section of brake pads (D) Minimum lining thickness (1) Backing plate (2) Brake lining (3) End plate (4) Bolt for end plate
Illustration 3 g00783032
(E) Uneven wear on brake linings
Remove the linings.
To help prevent abnormal lining wear, replace end plates (3) which are worn, bent or cracked. Replace backing plates (1) that are distorted.
Inspect bolts (4) for end plate for wear. Replace the bolts, if the bolts are worn.
Use the following procedure to inspect the brake linings.
Inspect the linings (2) for wear.
Replace linings (2) when thickness (D) of the linings is less than 3.2 mm (0.125 inch).
Inspect the linings for uneven wear (E) .
Replace the linings if the thickness of the two linings is significantly different.
Replace the piston and the housing if a piston is cocked in the bore.
Check that the surface of the disc is flat and parallel to the linings.
Check for oil or grease on the linings. If there is oil or grease on the linings, replace the linings.
Inspect the linings for cracks. Replace the linings if the linings are cracked.Note: Small cracks on the surface of the linings are normal when the caliper is used in high temperature conditions.Inspect for Leaks in the Caliper
Illustration 4 g00783422
(5) Fluid leaks in piston (6) Fluid leaks in bleeder screw (7) Fluid leaks in cylinder cap (8) Fluid leaks in inlet fitting
Table 2
Torque Chart    
Bleeder screws    
11.3 to 13.6 N m (100 to 120 lb in)    
Cylinder caps    
100 N m (75 lb ft) (minimum)    
Bolts for end plate    
224 to 285 N m (165 to 210 lb ft)    
Check the caliper for leaks at pistons (5) .
If fluid is leaking at a piston, disassemble the caliper. Inspect the piston, the bore, the O-rings and the backup rings. Provide service, as needed.
Check for leaks at cylinder caps (7) .
If fluid is leaking at a cylinder cap, tighten the cylinder cap, the inlet fitting and the plug. If the leak continues, disassemble the caliper.
Inspect the threads for the cylinder cap, the threads for the housing and the O-ring. Provide service, as needed.
Check for leaks at bleeder screws (6) .
If fluid is leaking at the bleeder screw, tighten the bleeder screw. If the leak continues, replace the bleeder screw.
Check for leaks at inlet fitting (8) .
If fluid is leaking at the inlet fitting, tighten the fitting. If the leak continues, replace the O-ring.Inspect the Caliper
Illustration 5 g00784073
(9) Micrometer (10) Piston (F) Outside