PUMP 2012026 - Caterpillar

Correction
After the location of the leakage is found, use the procedure that follows to correct brake problems.1. For hose, tube or fitting leaks; tighten, repair or replace connections as needed.2. If the leakage is in a master cylinder, replace seals (1), (2) and (3) of the master cylinder. It is also possible that some other defect, that can be easily seen, will need correction. Also, rippling (roughness) may be found in the bore of the master cylinder. This condition is not desired. Correct any damage or problem that can be easily found.3. If the leakage is in a wheel brake head assembly, replace seals (4) and (5) of the head assembly, or replace the complete head assembly.Remove Air From The Wheel Brake Hydraulic Circuit (Bleed The Brakes)
Make reference to on first page of AIR SYSTEM AND BRAKES TESTING AND ADJUSTING section.
Air must not be in the hydraulic circuit. Air in the system can prevent complete brake application and it is possible that the wheels on the machine can not be stopped. Keep both brake fluid reservoirs full of brake fluid during the air removal procedure.1. Start the engine and let the air pressure go up to normal pressure for operation. Keep the engine in operation during this procedure to make sure of correct air pressure.2. Push and hold the right brake pedal down.3. Loosen (open) bleeder screws (1) on the master cylinders.4. Tighten (close) bleeder screws (1) and release the right brake pedal.
Bleeder Screws For The Master Cylinders
(1) Bleeder screws for the master cylinders.5. Do Steps 2 thru 4 again until there is a constant flow of brake fluid (all of the air is removed) from each bleeder screw on the master cylinders.
Bleeder Screws For The Wheel Brake
(2) Bleeder screws.6. Push and hold the right brake pedal down. Bleed only one wheel at a time.7. Open bleeder screws (2) at a wheel brake.8. Close bleeder screws (2) and release the right brake pedal.9. Do Steps 6 thru 8 again until there is a constant flow of brake fluid from bleeder screw (2).10. Do Steps 6 thru 9 again at each wheel brake until all of the air is removed from the system.Hot Or Dragging Brakes
0 to 1380 kPa (0 to 200 psi) Gauge. 6.4 mm (.25 in.) diameter by 150 mm (6 in.) long bolt.
Make reference to on first page of AIR SYSTEM AND BRAKES TESTING AND ADJUSTING section.
Use the procedure that follows to correct a problem of hot or dragging brakes:
Location To Install Gauge
(1) Drain valve for the air reservoir. If the brake fluid pressure indicator is on, go to Step 9b.1. Install a 0 to 1380 kPa (0 to 200 psi) gauge in drain valve (1) of the air reservoir.2. Remove brake fluid pressure switch (2) and the indicator rod from the air/hydraulic cylinder. Use a 6.4 mm (.25 in.) diameter bolt that is 150 mm (6 in.) long, in place of the indicator rod. Two bolts can be used to check both master cylinders at