User manual HALDEX L30037 SERVICE MANUAL

[. . . ] Refer to pages 4 and 5 for detailed installation procedures. Figure 1 Steer axle with clamp bracket and flat anchor stud Figure 2 Steer axle with strap bracket Drive Axle Figures 3 and 4 show typical brackets for automatic brake adjuster applications on drive axle brake assemblies. Refer to pages 4 and 5 for detailed installation procedures. Figure 3 34° drive axle with strap bracket Figure 4 Mack drive axle with clamp bracket and flat anchor stud Note: Refer to fundamental parts identification and location on page 10. 2 Typical Applications Trailer Axle Figures 5-8 show typical brackets for automatic brake adjuster applications on trailer axle brake assemblies. Refer to pages 4 and 5 for detailed installation procedures. Figure 5 For 16-1/2" Brake Assemblies Figure 6 For 12-1/4" Brake Assemblies Figure 7 Integral cam support anchor bracket for 12-1/4" and 16-1/2" brakes Figure 8 Bolt-on cam support anchor bracket for 12-1/4" and 16-1/2" brakes 3 Note: Refer to fundamental parts identification and location on page 10. S-ABA Installation Procedures Note: Configuration of anchor bracket and brake adjuster housing may vary, depending upon axle. Refer to typical applications on Pages 2 and 3. Step 1 Note: Block wheels to prevent vehicle from rolling. [. . . ] The difference between the fully retracted and drum contact measurement "B"­"A" (fig. The free stroke range should fall between 3/8"­3/4". Free Stroke Within Range If the free stroke is good, but the applied stroke is too long, there is probably a problem with the foundation brake. Check the following and reference CVSA out-of-service criteria: Component Brake drums Brake shoes Brake shoes Brake shoes Brake shoes Cam bushings Camshaft Camshaft Camshaft Chamber bracket Clevis yoke and pin Return springs Rollers Rollers Spider anchor pins Cracked or out of round Shoe span out of spec Uneven lining wear Shoe pad missing Cracked shoes Excessive movement Flat spots on cam head Cracked/broken splines Worn bearing journals Broken/bent Worn Broken/stretched or missing Flat spots, grooved pin/worn Wrong size Grooved or scored/worn Cause Replace or check drum run out Refer to OEM specs and replace if necessary Check spider concentricity Remove & replace shoes Remove & replace shoes Remove & replace cam bushings per OEM specs Replace camshaft Replace camshaft Replace camshaft Replace bracket Remove & replace Remove & replace springs Remove & replace roller and pin Remove & replace with correct parts Replace spider or pins, as appropriate for OEM Action 7 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: Component Cause Action Camshaft Camshaft bushings Camshaft bushings Air chamber return springs Air chamber push rod Air system Shoe return springs Automatic brake adjuster Binding Excessive movement Binding shaft Broken, weak, missing Binding on chamber housing Not exhausting completely Broken, weak, missing Unknown Automatic brake adjuster Unknown Remove, replace, lubricate camshaft Remove and replace cam bushings per OEM specs Lubricate camshaft bushings or replace Replace chamber Check adjuster for proper shimming and air chamber position for proper adjuster arm length Check for cause of air problem and repair Replace springs Check automatic brake adjuster for proper installation. Refer to Automatic Brake Adjuster Checking Procedures and Operational Check on pages 9 & 10. Free Stroke Below the Range If the free stroke is less than 3/8", a dragging brake can occur. Check the following: Component Cause Action Wheel bearing Automatic brake adjuster Out of adjustment Unknown Automatic brake adjuster Unknown Readjust per OEM specs Check automatic brake adjuster for proper control arm position. Refer to Automatic Brake Adjuster Checking Procedures and Operational Check on pages 9 & 10. Free Stroke = B minus A Applied Stroke = C minus A (Fully Retracted) (Drum Contact Using a Lever) (Brake Application at 90-100 PSI reservoir pressure. ) A B C Figure 13 Stroke Measurements (taken from face of air chamber to center of clevis pin) 8 Automatic Brake Adjuster Checking Procedures If the brake adjuster is not maintaining the proper applied stroke, before removing the brake adjuster, check the condition of the foundation brake (see pages 7 & 8). If rotation of the adjustment hex is not observed, refer to Foundation Brake Operational Check and Troubleshooting Procedures on pages 7 & 8. If foundation brake assembly checks out okay and hex still does not turn, check control arm and mounting bracket for possible worn, bent or broken components. If the control arm and mounting bracket check out okay, replace the adjuster and hardware per Installation Instructions on pages 4 & 5. 9 Off Vehicle Inspection Component Adjuster not functioning properly Cause Low clutch torque Action Place adjuster arm in vise. Rotate the 7/16" adjustment hex counterclockwise one full turn to check de-adjustment torque. Rotate the control arm counterclockwise until the control arm rotates to an INTERNAL STOP. Manually pull the brake adjuster control arm clockwise then push back counterclockwise. The hex will move in a clockwise direction when the control arm of the brake adjuster is pushed back counterclockwise. If adjuster has passed the above checks, re-install adjuster on vehicle, with new hardware. Control Arm slippage Unknown Worn/missing control arm wear bushing, and anchor stud pin, if applicable. Typical Parts Identification and Location Anchor Bracket Anchor Stud Pin Anchor Bracket Control Arm (Single Bend) Wear Bushing Anchor Stud Pin Adjustment Hex Nut Wear Bushing Control Arm 10 Torque Specifications Note: Tighten all fasteners to manufacturer's recommendations unless otherwise specified below. Flat Anchor Stud Pin Torque to 40-50 ft. when installed Round Anchor Stud Pin with Fabricated Ring Clamp Torque to 15-20 ft. when installed Round Anchor Stud Pin with Slide Nut Torque to 15-20 ft. Will the side of the brake adjuster with the face plate always face in? No. Always install with the adjusting hex pointing away from the air chamber. 2. Can I vary the amount of lining-to-drum clearance by moving the control arm? No, that clearance is set at the factory. If long or short stroke continues, please refer to the foundation brake checking procedures on pages 9 & 10 of this manual. 9. Can I use an air ratchet on the adjuster? It takes approximately 20 lb. [. . . ] Make sure the control arm, anchor bracket and wear items are in good working order to assure the adjuster will operate as designed. 18. If automatic adjustment stops, can I operate as a manual brake adjuster? Yes. Normal wear items like anchor stud pins and wear bushings are available. Otherwise, contact Haldex Technical Assistance for the appropriate bracket kit at 1-800-643-2374. No. Completely check out foundation brake and adjuster to determine cause of problem. [. . . ]