background image

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 

(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 2: ...oundation brake Brake components such as s cams bushings return springs actuators drums and adjuster installation MUST be within manufacturer s specifications Adjuster control arms wear bushings or at...

Page 3: ...Location 10 Torque Specifications 11 Frequently Asked Questions 12 Additional Parts and Service Information 13 Important Notice This symbol is used throughout this manual to call attention to procedur...

Page 4: ...ake Applies When the brake is applied the adjustment regulator rotates through the normal clearance angle and the shoes contact the drum The torque increases and the wormshaft is moved axially causing...

Page 5: ...or automatic brake adjuster applications on drive axle brake assemblies Refer to pages 4 and 5 for detailed installation procedures Figure 1 Steer axle with clamp bracket and flat anchor stud Figure 3...

Page 6: ...detailed installation procedures 3 Figure 5 For 16 1 2 Brake Assemblies Note Refer to fundamental parts identification and location on page 10 Typical Applications Figure 7 Integral cam support ancho...

Page 7: ...er hole location while 6 and 6 1 2 length adjusters utilize the longer hole locations Do not tighten anchor bracket fasteners at this time Apply Anti Seize type lubricant to camshaft splines Install t...

Page 8: ...anually adjusted at this time Rotate the adjusting hex clockwise until the lining lightly contacts the drum Back off the adjuster by turning the adjusting hex counter clockwise 1 2 of a turn Figure 12...

Page 9: ...a 429 prefix Moly disulfide grease should not be used because it may affect the function of the internal friction clutches and reduce the reliability of the automatic adjustment In no case should the...

Page 10: ...released measure from the face of the chamber to the center of the clevis pin A Figure 13 Use a lever to move the brake adjuster until the brake shoes contact the drum B Figure 13 The difference betwe...

Page 11: ...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 Readj...

Page 12: ...icle from rolling Ensure reservoir pressure is at 90 100 psi Check that the push rod is fully retracted apply air to release spring brake If air is not available spring brake must be manually caged ba...

Page 13: ...the control arm slippage clockwise and counterclockwise while observing the internal sleeve If slippage between the control arm and the internal sleeve is observed replace the brake adjuster Unknown...

Page 14: ...nstalled Round Anchor Stud Pin with Slide Nut Torque to 15 20 ft lbs when installed Strap Style Bracket Torque to 8 12 ft lbs when installed U Bolt Style Bracket Torque to 20 30 ft lbs when installed...

Page 15: ...foundation brake and not true pushrod stroke 7 Some brake chambers have round port openings and some square what is the difference Standard brake chambers are identified by round ports Long stroke ch...

Page 16: ...Information Installation and Maintenance Wall Chart L60047 Service Manual Truck Trailer L30037 Installation Tips Automatic Brake Adjuster Pocket Size L20397 Parts Information Parts and Cross Reference...

Page 17: ...14 Notes...

Page 18: ...15 Notes...

Page 19: ......

Page 20: ...ockholm Stock Exchange Haldex has annual sales of approximately 3 9 billion SEK and employs about 2 200 people United States 816 891 2470 Canada 519 621 6722 Mexico 52 81 81569500 To learn more contac...

Reviews: