 |
Personal injury or death can result if two persons are not used in the following procedure. |
 |
|
Personal injury or death can result from a parking brake malfunction. Do not operate the machine if the parking brake does not function correctly. Be sure the parking brake components are adjusted correctly before attempting to return the machine to service. |
|
|
Personal injury or death can result from sudden machine movement. Sudden movement of the machine can cause injury to persons on or near the machine. Prevent possible injury by performing the procedure that follows before working on the machine. |
|
Machine Preparation
- Park the machine on a smooth, level surface.
- Place the transmission control in the NEUTRAL position.
- Lower the bucket and/or any work tools to the ground.
- Engage the parking brake.
- Shut off the engine.
- Place blocks in front of the wheels and behind the wheels.
- Install the steering frame lock.
 | |
| Illustration 1 | g00501895 |
Steering Frame Lock (1) Steering frame lock in LOCKED position | |
- Allow only authorized personnel on the machine. Keep unauthorized personnel off the machine and in clear sight of the operator.
- Disengage the parking brake.
- Remove the parking brake. The parking brake must be disassembled in order to perform the adjustment procedure.
ReferenceFor additional information on removing and disassembling the parking brake, refer to Disassembly and Assembly, "Parking Brake - Remove and Install" for the machine that is being serviced.
Note: Be sure to avoid getting any grease or dirt on the brake shoes. Grease and dirt on the brake shoes greatly reduces the effectiveness of the parking brake.
Adjustment Procedure
- Place brake drum (2) on a flat surface. Make sure that the large diameter of the brake drum is facing upward. Place brake group (4) into the brake drum. Make sure that camshaft (3) is facing upward.
 | |
| Illustration 2 | g02423659 |
Parking Brake and Parking Brake Group (2) Brake drum (3) Brake camshaft (4) Brake group (5) Spring (6) Starwheel (7) Brake shoes | |
- Rotate starwheel (6) in order to move brake shoes (7) outward. Rotate the starwheel until the brake shoes contact brake drum (2). Make sure that the brake shoes stay above the radius at the bottom of the brake drum.
- Rotate starwheel (6) so that the brake shoes (7) press against brake drum (2). The force of the brake shoes should be sufficient to hold the shoes to the drum when you lift brake group (4) upward.
- Lift brake group (4) upward. Place the brake drum and the brake group on the flat surface.
- Rotate the starwheel (6) for 12 clicks in order to release the pressure of the brake shoes (7) on the brake drum (2) .
- Pressurize the actuator to extend the actuator rod. The pressure should be 12500 to 15000 kPa (1800 to 2200 psi). Do not exceed the maximum pressure of 25000 kPa (3600 psi).
- Adjust rod end (10) to obtain dimension (A + B) of 160 mm (6.3 inch). Do not torque locknut (9) .
 | |
| Illustration 3 | g02423796 |
(8) Actuator shaft (9) Locknut (10) Rod end | |
- Position lever (13) on the splined end of camshaft (14). Push lever (13) lightly by hand to take slack out of the system. Do not extend the brake shoes out to the drum. Align the hole in lever (13) with hole in rod end (10) .
 | |
| Illustration 4 | g02423817 |
Side View of Parking Brake and Actuator (11) Cotter (12) Pin (13) Lever (14) Splined end of brake camshaft (15) Bolt | |
- Secure lever (13) on camshaft (14) with bolt (15). Install pin (12), washer, and cotter (11). Tighten locknut (9) on actuator shaft (8) .
- Apply brake by releasing the hydraulic pressure in the actuator. Measure the length of the actuator stroke (B). Length (B) should be within 25 to 38 mm (0.98 to 1.50 inch). If the stroke is within these limits, the brake adjustment is complete. If the stroke is outside these limits, proceed to Step 11.
- Verify that lever hole and rod end hole are aligned with the brake released. Remove pin (12). Push lever (13) lightly by hand toward the actuator. Verify that the pin holes line up when the slack is removed from the system. If the pin holes are not aligned, readjust rod end (10). Repeat Step 7 through Step 10.