and COMPLETE RELEASES (the number of applications depends on how much the slack was de‑adjusted).
BRAKE MAINTENANCE INSPECTION
Note: Make certain the vehicle has been prepared according to the instructions under the heading GENERAL SAFETY GUIDELINES.
The following test can be used to inspect the maintenance condition of the foundation brake and to determine how much of the chamber stroke is caused by the condition of the foundation brake.
1.Always chock the wheels to keep vehicle from moving.
2.Raise the axle so the wheel can be rotated.
3.Adjust the slack adjuster to produce light brake drag with wheel rotation.
4.Apply the brake to 80‑90 psi and measure the stroke (See Item 3 of In Service Inspection for pressure tips).
5.If the stroke significantly exceeds the values shown in the chart, the brake may be out of the norm and brake maintenance may be required.
AL Factor | 15"x4" | 16.5"x7" | 16.5"x7" |
| |
| Front | Tractor, Truck | Trailer |
| |
| Brake | or Bus Brake | Brake |
| |
|
|
|
|
|
|
12 X 5.0" | 1/2" | N/A | N/A |
| |
12 X 5.5" | 1/2" | N/A | N/A |
| |
|
|
|
|
|
|
16 X 5.0" | 5/8" | 1/2" | N/A |
| |
16 X 5.5" | 3/4" | 1/2" | N/A |
| |
|
|
|
|
|
|
16 X 6.0" | 7/8" | 5/8" | N/A |
| |
20 X 5.0" | 5/8" | 1/2" | 3/8" |
|
|
|
|
|
|
|
|
20 X 5.5" | 3/4" | 5/8" | 1/2" |
|
|
20 X 6.0" | 7/8" | 3/4" | 5/8" |
|
|
|
|
|
|
|
|
24 X 5.0" | N/A | 5/8" | 1/2" |
|
|
24 X 5.5" | N/A | 5/8" | 5/8" |
|
|
|
|
|
|
|
|
24 X 6.0" | N/A | 3/4" | 5/8" |
|
|
30 X 5.0" | N/A | 3/4" | 5/8" |
|
|
30 X 5.5" | N/A | 7/8" | 3/4" |
|
|
30 X 6.0" | N/A | 1" | 7/8" |
|
|
|
|
|
|
|
|
ASA‑5® SLACK ADJUSTER REMOVAL
Note: Make certain the vehicle has been prepared according to the instructions under the heading GENERAL
SAFETY GUIDELINES.
1.If the ASA‑5® slack adjuster is equipped with the easy‑on yoke assembly illustrated in Figure 3:
A.Loosen the brake actuator push rod jam nut and run it back on the brake actuator push rod approximately 5/8 inch.
B.Loosen the easy‑on yoke adapter and run it back on the brake actuator push rod until it is free of the yoke.
C.Rotate the manual adjustment hex counterclockwise until the ASA‑5® slack adjuster is clear of the brake actuator push rod.
Note: Considerably more torque is required to rotate the manual adjustment hex counterclockwise than is necessary to rotate it clockwise. The torque may be as high as 70 foot pounds.
2.If the ASA‑5® slack adjuster is equipped with the quick‑connect yoke assembly illustrated in Figure 4:
A.Rotate the ASA‑5® slack adjuster's manual adjustment hex counterclockwise until the brake actuator push rod just begins to move out of the actuator.
B.Pinch the legs of the retaining ring together and pull the ASA‑5® slack adjuster away from the brake actuator push rod until the adapter bushing is free of the yoke. Remove the retaining ring from the adapter bushing.
C.Rotate the manual adjustment hex counterclockwise until the ASA‑5® slack adjuster is clear of the brake actuator push rod.
3.Remove the ASA‑5® slack adjuster from the camshaft of the foundation brake by removing the retaining clip and any spacers or washers that may be present.
DISASSEMBLY
GENERAL
A reasonable level of cleanliness should be observed when working on the ASA‑5® slack adjuster. Clean the exterior before disassembly.
The following disassembly and assembly procedure is presented for reference purposes and presupposes that a rebuild or repair of the ASA‑5® slack adjuster is being undertaken. Several replacement parts and maintenance kits are available which do not require full disassembly. The instructions provided with these parts and kits should be followed in lieu of the instructions presented here.
1.Clamp the ASA‑5® slack adjuster ARM in a bench vise. Do not clamp across the portion of the body that contains the adjuster assembly or worm gear. Using a wire brush, thoroughly clean the exterior of the slack adjuster paying particular attention to the area around the manual adjustment hex and its retaining ring. Wipe all loose contaminants away before proceeding.
2.Remove the cotter pins and washers from the yoke pin and link pin.
3.Remove the yoke pin and link pin and separate the yoke from the ASA‑5® slack adjuster.
4.If the ASA‑5® slack adjuster has a yoke pin bushing, press it out of the slack adjuster arm.
5.No further disassembly of the ASA‑5® slack adjuster is permitted.
7
