User manual BENDIX E-12-E-15 BRAKE VALVE

[. . . ] The supply, delivery and exhaust ports of the E-12TM/E-15TM brake valves are identified by designations cast into the valve body adjacent to their associated port. The primary supply and delivery ports are located in the upper body portion while the secondary supply and delivery ports are located in the lower body portion of the valve. The primary circuit of the valve is similar in operation to a standard single-circuit air brake valve and under normal operating conditions the secondary circuit is similar in operation to a relay valve. Both the primary and secondary circuits of the brake valve use a common exhaust protected by an exhaust diaphragm. OPERATION APPLYING: NORMAL OPERATION-PRIMARY CIRCUIT PORTION When the brake treadle (26) is depressed, the plunger (27) exerts a force on the spring retainer (7), graduation spring (8) and primary piston (2). [. . . ] Never connect or disconnect a hose or line containing pressure; it may whip. Never remove a component or plug unless you are certain all system pressure has been depleted. 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. Prior to returning the vehicle to service, make certain all components and systems are restored to their proper operating condition. VEHICLE PREPARATION 1. Park the vehicle on a level surface and block the wheels and/or hold the vehicle by means other than the air brakes. 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. Carefully remove and discard the exhaust diaphragm retainer (24) and exhaust diaphragm (25) from the lower body. Note: Some E-12TM & E-15TM brake valves have threaded exhaust ports in lieu items 24 & 25. Using finger force, push the piston (2) into the body until the piston retaining ring (1) is fully visible. Remove the piston retaining ring (1), taking care not to damage the piston bore in the body. Remove and discard the o-rings (3 & 5) and both wear rings (4) from the piston (2). Place the piston on a flat surface and using finger force, depress and hold the spring retainer (7), then remove and discard the retaining ring (6) from the piston (2). Gently release the spring retainer (7), allowing it to rise out of the piston. Remove the spring retainer (7) and graduating spring (8) from the piston (2). 12. Remove and discard the rubber spring (9) from the interior of the piston (2). Note: The rubber spring (9) is installed in the E-12TM brake valve only. Remove and discard the special beveled retaining ring (10) from the piston (2) while manually holding and compressing the valve seat (11) in place. Slowly release the valve seat (11), allowing it to rise out of the piston (2). Remove and discard the valve assembly (13) along with its o-ring (15) from the piston (2). Remove the valve assembly return spring (14). CLEANING & INSPECTION 1. [. . . ] Make certain the beveled retaining ring (10) is completely seated in its groove in the lower body. Install the assembled secondary piston (18) in the upper body making certain that the o-rings (19 & 20) are not damaged in the process. Join the assembled upper and lower body halves noting the relationship marked in Disassembly step 2. Secure the body halves together using the four 1/4" cap screws (16) and torque to 30 to 60 pound inches. [. . . ]