User manual BENDIX DOUBLE ANCHOR PIN CAM BRAKE

[. . . ] ® Bendix® Double Anchor Pin Cam Brake FIGURE 1 GENERAL DESCRIPTION The Bendix 16-1/2" x 7" double anchor pin cam brake is designed for use on heavy duty highway vehicles. It is a mechanically actuated, leading /trailing shoe brake with a fixed position cam and anchors. The brake consists of two fabricated steel shoe assemblies individually anchored to a cast iron torque spider and actuated by a single forged cam shaft. Two retaining springs secure the shoe assemblies to their respective anchor pins. [. . . ] One at the end of the actuator bracket and one at the cam entrance in the spider. Remove the spider from the axle flange by removing the twelve bolts, nuts, and lockwashers that secure it. To facilitate assembly, note or mark the relationship of the spider to the axle (driver or curb side) and the orientation on the axle flange. Remove and discard the two cam shaft bushings located in the same area as the seals in Step 11. NOTE: Prior to removal, see the "Inspection of Parts" section, Steps 1B and 3B. CLEANING OF PARTS After disassembling the foundation brake, Wash the metallic components in mineral spirits and wipe dry. Be careful not to get any foreign material, especially grease on the brake shoes or interior of the brake drum. Use a wire brush to remove heavy contamination from the spider and outside of the brake drum. Check assembly for bent actuator bracket and broken or cracked cam tube welds. Bearing surfaces should be smooth and free of any pitting or fractures. Insert cam shaft and measure looseness at both ends with a dial indicator. If more than . 020" movement is noted, replace bushings and/or cam shaft. NOTE: If it is determined that a bushing requires replacement, both cam shaft bushings should be replaced. If the shaft shows wear or roughness that is visible or roughness that can be detected by feel, it must be replaced. Inspect cam head for cracks, and its roller surfaces for flat spots, brinneling, or ridges. Note unusual wear patterns which may indicate an out-of-square condition. Inspect for cracked or broken surfaces an the spider at the cam, anchor pins, and mounting bolt holes. (See 1 B) Bearing surface should be smooth and free of any pitting or fractures. NOTE: If it is determined that the bushing requires replacement, change both cam shaft bushings. Inspect rollers and pins for flat spots, galling, broken or cracked surfaces. Replace as necessary. 5 NOTE: BOTH LIP SEALS POINT THE SAME DIRECTION LIP TOWARD SLACK ADJUSTER . 094" 6" LIP SEAL CAM END FIGURE 8 - CHECKING SLACK ADJUSTER BACKLASH SLACK ADJUSTER END ACTUATOR BRACKET AND CAM TUBE SPIDER FIGURE 9 - SEAL INSTALLATION LIP SEAL 6. Check shoes for bent shoe webs, cracks in shoe table welds or webs, and elongated rivet holes. Measure the shoe span by loosely installing the anchor pin and cam roller in the appropriate ends of the shoe web. [. . . ] Rust often develops on the surface of the shoe table under the brake lining or blocks. In addition, scale may form from salt on the highways, or tar and oil may find their way into the brake assembly. The best procedure is to steam clean the entire shoe or put it in a degreaser. USE RIVETS OF CORRECT LENGTH AS SHOWN TOO SHORT FIGURE 10 CORRECT TOO LONG After cleaning the shoe, the shoe table should be scraped clean of rust and scale. At the same time, the entire shoe should be examined to see whether it is worn or bent. [. . . ]