Component
Cause
Action
Air Chamber Pushrod
Binding on chamber housing
Check adjuster for proper shimming and air
chamber position for proper adjuster arm length
Air Chamber Return Springs
Broken, weak, missing
Replace chamber
Air System
Not exhausting completely
Check for cause of air problem and repair
Automatic Brake Adjuster
Unknown
Check automatic brake adjuster for proper
installation (refer to Pages 4 & 5 and 9 & 10).
Camshaft
Binding
Remove, replace, lubricate camshaft
Camshaft Bushings
Excessive movement
Remove and replace cam bushings per OEM specs
Binding shaft
Lubricate camshaft bushings or replace
Shoe Return Springs
Broken, weak, missing
Replace springs
Component
Cause
Action
Automatic Brake Adjuster
Unknown
Check automatic brake adjuster for proper
installation (refer to Pages 4 & 5 and 9 & 10).
Wheel Bearing
Out of adjustment
Readjust wheel bearing per OEM specs
Free Stroke Above The Range
If the free stroke is above the range and the applied stroke is too long, there is a problem with the
foundation brake or the adjuster. Check the following and reference CVSA out-of-service criteria:
Free Stroke Below The Range
If the free stroke is less than 3/8”, a dragging brake can occur. Check the following and reference
CVSA out-of-service criteria:
Free
Stroke = B minus A
A
(Fully Retracted)
B
(Drum Contact Using a Lever)
C
(Brake Application at 90-100 PSI
reservoir pressure.)
Figure 13
Stroke Measurements
(taken from face of air
chamber to center of
clevis pin)
8
Free Stroke (cont’d)
Summary of Contents for S-ABA
Page 1: ...Service Manual S ABA Self Setting Automatic Brake Adjusters Truck and Trailer Applications...
Page 17: ...14 Notes...
Page 18: ...15 Notes...
Page 19: ......