User manual BENDIX MV-1 MODUTROL

[. . . ] Port identification for the push-pull module is shown on Fig. 9. OPERATING MODE NORMAL RUN V-1 BUTTON IN. DELIVERY SUPPLIES BOTH SECTIONS OF V-3 (PP-8TM AND SV-1TM VALVE). V-2 BUTTON IN. DELIVERY TO TRACTOR SPRING BRAKES AND TO PILOT SECTION OF PILOT VALVE (SV-1TM). [. . . ] 2 and in the descriptive write-up which follows. OPERATING AND LEAKAGE TESTS Prior to testing for leakage and function of the components in either module, the knobs must first be removed from the push-pull valves and then any panel cover plate or escutcheon plates removed so that the top of the spool assemblies and the retaining rings that hold the spools in place are visible. For an operational test of the push-pull module, a test gauge should be connected to a tractor spring brake line and one to the trailer supply hose. Function of the push-pull valves may then be checked per the chart, Fig. 3. INITIAL CHARGE Without air pressure in any part of the system, valve buttons V-1, V-2, and V-3 are out. When system pressure reaches 60 psi, valve buttons V-1 and V-3 may be pushed in and air will be delivered through valve V-3 charging the trailer system. The trailer parking brakes (whether spring or air applied) will release; however, the tractor spring brakes remain applied. Pushing valve button V-2 in will release tractor spring brakes. NORMAL RUN POSITION With valve buttons V-1, V-2, in and V-3 out, air is being supplied to the trailer, all parking brakes are released and the system is in the normal run position. ACTUATION OF TRAILER BRAKES ONLY To actuate only the trailer brakes, valve button V-1 is pulled out. This action exhausts the air supply from the trailer supply line, causing the tractor protection valve to close. Typical use of this mode would be to apply trailer brakes before uncoupling. This mode would be used during a tractor "bob-tail" operation. PUSH-PULL MODULE OPERATIONAL TEST AIR DELIVERY AIR DELIVERY VALVE TO TRACTOR TO TRAILER SUPPLY POSITION SPRING SUPPLY PRESSURE V-1 V-2 V-3 BRAKES HOSE 100 PSI IN OUT OUT ZERO ZERO IN IN OUT 100 PSI 100 PSI IN OUT IN ZERO 100 PSI OUT IN* OUT 100 PSI ZERO 100 PSI IN IN OUT 100 PSI 100 PSI REDUCING TO 35-45 PSI OUT OUT OUT ZERO ZERO *When V-2 is pushed IN, V-3 should pop OUT. FIGURE 3 PUSH-PULL MODULE LEAKAGE CHART 100 PSI SUPPLY PRESSURE FOR ALL TESTS VALVE POSITION V-1 V-2 V-3 Leakage Symptoms Correction OUT OUT OUT Valve V-1 at S-1 Replace spool (Around Stem) assembly in V-1 Valve V-2 at S-2 Replace spool (Around Stem) assembly in V-2 OUT OUT OUT Valve V-1 at S-3 Replace spool assembly in V-1 Valve V-2 at S-4 Replace spool assembly in V-2 Exhaust Port P-6 Replace spool in V-1 or V-2 as required IN OUT OUT Valve V-3 at S-5 Replace spool in V-3 Valve V-3 at S-6 Replace spool in V-3 Exhaust Port P-6 Replace spool in V-1 or V-3 as required OUT IN OUT Exhaust Port P-6 Replace spool in V-2 or V-3 as required IN OUT IN Exhaust Port P-6 Replace spool assembly in V-1 or V-3 MANUAL SYSTEM PARK To apply the parking brakes on both tractor and trailer, valve button V-2 is pulled out. NOTE: If the trailer is not equipped with spring brakes (pre-121), it is desirable to release the trailer emergency application and provide a "demonstrated park" (proven holding ability via tractor spring brakes only). This may be done by positioning valve button V-1 "IN, " V-2 button "OUT, " and pushing button V-3 "IN. " This action recharges the trailer supply line, releases the trailer brakes and allows the tractor spring brakes to demonstrate their ability to hold both the tractor and trailer in a parked position. AUTOMATIC SYSTEM PARK If the supply or delivery pressure for the push-pull module is reduced, either valve buttons, V-1 or V-2, or both will pop out automatically when the supply pressure is between 35-45 psi. When button V-1 pops out, the trailer supply line will vent to atmosphere, applying trailer brakes; should button V-2 pop out, the tractor spring brakes will also apply as well as the trailer. FIGURE 4 3 VALVE V-1 VALVE V-2 VALVE V-3 S-1 S-3 S-2 S-4 S-5 S-6 P-6 FIGURE 5 - PUSH-PULL VALVE LEAKAGE KEY AUXILIARY MODULE LEAKAGE CHART P-2 P-3 (SUPPLY) OPERATING MODE (SUPPLY CHARGED TO 100 PSI) VALVE POSITION T-1 T-2 OFF OFF Leakage Symptoms S-1 S-4 Exhaust Hole Exhaust Hole Correction spool assy. spool assy. P-5 (DELIVERY TO TRAILER AIR SUPPLY ON P-6 (EXHAUST) ON Exhaust Hole Exhaust Hole Replace in T-1 Replace in T-2 P-7 Replace in T-1 P-8 Replace in T-2 P-7 Replace in T-1 P-8 Replace in T-2 FIGURE 6 - TRACTOR SPRING BRAKE DELIVERY FIGURE 7 4 VALVE T-1 S-1 VALVE T-2 P-7 P-8 S-4 FIGURE 8 SUPPLY P-1 P-2 T-2 DELIVERY (P-3) P-5 T-1 DELIVERY (P-4) P-6 SUPPLY FIGURE 9 5 Leakage of the push-pull valves may then be checked per the chart shown on Fig. A normal supply pressure of 100 psi at supply port P-3 is assumed for these leakage tests. Leakage may be checked by a soap solution. NOTE: Take care in not allowing excessive soap solution in valve. The auxiliary on/off module may be checked for leakage per chart shown on Fig. 7 and key 8, again assuming a 100 psi supply pressure at any one of the four supply ports. 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. [. . . ] Remove the retaining ring from the cavity involved, pull out the spool assembly and replace with a new spool. The spool will normally be packaged with pre-lubricated o-rings; however, should additional lubricant be required, BW-650M (Dow Corning 55-M) should be used (Bendix piece number 291126). The push-pull assemblies may be installed without regard to radial orientation; however, the lever type on/off spool assemblies must be installed with the operating lever in either the horizontal or vertical position. NOTE: The segment on the bottom of the spool must match the appropriate notch in the bottom of the cavity. [. . . ]