User manual BENDIX R-12DC DBL CHECK RELAY VALVE

[. . . ] The exhaust remains closed as the service line pressure balances the delivery pressure. As delivered air pressure is changed, the valve reacts instantly to the change, holding the brake application at that level. valuable guide in determining the best maintenance interval for air brake system components. At a minimum, the valve should be inspected every 6 months or 1500 operating hours, whichever comes first, for proper operation. Should the valve not meet the elements of the operational tests noted in this document, further investigation and service of the valve may be required. EXHAUST OR RELEASE When air pressure is released from the service port and air pressure in the cavity above the relay piston is exhausted through the brake valve. [. . . ] CAUTION: The valve body may be lightly clamped in a bench vise during disassembly, however, over-clamping will result in damage to the valve and result in leakage and/or malfunction. If a vise is to be used, position the valve so that the jaws bear on the supply ports on opposing sides of the valve's body. 4 5. Remove piston (9) from the body (10) and retain for reuse. Remove and discard o-ring (8) from piston (9). Depress and hold the exhaust cover assembly (16) and remove and discard retaining ring (17) from the valve body (10). Slowly release the holding force on the exhaust cover assembly (16) to relax the spring. Remove and discard the following parts: a. Install retainer (12) on inlet exhaust valve (11) and insert both in the body (10). Install exhaust cover assembly (16) in the body (10). Depress and hold the exhaust cover assembly in the body. Install retaining ring (17) in the body (10). Make certain the retaining ring is completely seated in the groove in the body. Install o-ring (5) on double check cover (6), install spring (2), guide (3) and double check diaphragm (4) in cover (1). Install cover (1) and torque torx head screws to 80-100 in. Referring to the marks made during disassembly, install cover (1). Install the mounting bracket (not shown) on the cover (1). Install the four cap screws in the cover (1) and torque to 80-100 inch pounds. Test the valve as outlined in the Operational and Leakage Test section before returning the valve to service. CLEANING AND INSPECTION 1. Wash all metal parts in mineral spirits and dry them thoroughly. (Note: When servicing the R-12DCTM valve, all springs and all rubber parts should be replaced. ) 2. Inspect all metal parts for deterioration and wear, as evidenced by scratches, scoring and corrosion. Inspect the exhaust valve seat on the relay piston for nicks and scratches which could cause excessive leakage. [. . . ] For assembly, hand wrenches are recommended. Prior to assembly, lubricate all o-rings, o-ring bores and any sliding surface with a silicone lubricant equivalent to Dow Corning #10. Wash all remaining parts in mineral spirits and dry thoroughly. Using the lubricant provided in this kit, lightly lubricate all o-rings, o-ring grooves, body bores any sliding surfaces. [. . . ]