User manual BENDIX SL-3-SL-4 STOP LIGHT SWITCH

[. . . ] Experience is a valuable guide in determining the best maintenance interval for air brake system components. At a minimum, the SL-3TM/ SL-4TM switch should be inspected every 6 months or 1500 operating hours, whichever comes first, for proper operation and electrical connections. Should the SL-3TM/SL-4TM switch not meet the elements of the operational tests noted in this document, further investigation and service of the valve may be required. 1 OPERATION When a brake application is made, air pressure from the brake valve enters the cavity below the diaphragm. [. . . ] Secure terminal screws with washers and nuts, or terminal clips, as the case may be. Position terminals (9) in cover (8) and secure with washers and nuts or terminal clips. O-ring diaphragm should be installed with its flat side adjacent to the piston. Place gasket (15) in place on body and contact strip (12) on piston (13). Install with pipe tap pointing to the ground and keep it high for adequate drainage. Keep the stop light switch terminals away from frame members to avoid grounding. Connect the pipe tap to the brake chamber supply line so that the stop light switch will operate whether the foot or hand valve is applied. DISASSEMBLY (SL-3TM SWITCH) 1. Using a large end wrench on cover flats, turn cover (1) in a counterclockwise direction and remove from body. Remove terminal nuts, terminals (2) and terminal connector (7) from cover. Remove spring (3), plunger (4), washer (5) and diaphragm (6) from body. Remove spring (11), contact strip (12), piston (13) and o-ring diaphragm (14) from body. TEST OF REBUILT STOP LIGHT SWITCH Both operating and leakage tests, as indicated under section headed "Testing for Serviceability", must be made after rebuilding or repairing the stop light switch. No leakage is permissible at the stop light switch with the brakes applied. The stop light switch contact should close with not more than 7 pounds of air pressure. 2 PRECAUTIONARY NOTE: WARNING!PLEASE READ AND FOLLOW THESE INSTRUCTIONS TO AVOID PERSONAL INJURY OR DEATH: When working on or around a vehicle, the following general precautions should be observed at all times. Park the vehicle on a level surface, apply the parking brakes, and always block the wheels. Stop the engine and remove ignition key when working under or around the vehicle. [. . . ] must be of equivalent size, type and strength as original equipment and be designed specifically for such applications and systems. Components with stripped threads or damaged parts should be replaced rather than repaired. Do not attempt repairs requiring machining or welding unless specifically stated and approved by the vehicle and component manufacturer. [. . . ]