PREVOST H3-41 Maintenance Manual page 406

SECTION 12: BRAKE AND AIR SYSTEM
12.1.1 Compressor Removal and Installation ................................................................................................. 16
13. MISCELLANEOUS VALVES .......................................................................................................................... 17
13.1 EMERGENCY / PARKING BRAKE CONTROL VALVE (PP-1) ............................................................................. 20
13.2 OPTIONAL EMERGENCY / PARKING BRAKE OVERRULE CONTROL VALVE (RD-3) ......................................... 20
13.3 FLIP-FLOP CONTROL VALVE (TW-1).............................................................................................................. 20
13.4 DUAL BRAKE APPLICATION VALVE (E-8P)..................................................................................................... 21
13.4.1 Brake Pedal Adjustment....................................................................................................................... 21
13.4.2 Maintenance ........................................................................................................................................ 21
13.5 STOPLIGHT SWITCHES .................................................................................................................................. 21
13.6 PARKING BRAKE ALARM SWITCH ................................................................................................................. 21
13.7 BRAKE RELAY VALVE (R-14) .......................................................................................................................... 22
13.8 ANTILOCK TRACTION RELAY VALVE (ATR-6)................................................................................................. 22
13.9 SPRING BRAKE VALVE (SR-7) ........................................................................................................................ 22
13.10 PRESSURE PROTECTION VALVE (PR-4) ......................................................................................................... 23
13.11 SHUTTLE-TYPE DOUBLE CHECK VALVE (DC-4) .............................................................................................. 23
13.12 PRESSURE REDUCING VALVE RV-3 ............................................................................................................... 23
13.13 ANTILOCK MODULATOR (M-32QR) .............................................................................................................. 24
13.14 INVERSION VALVE (TR-2, TR-3) .................................................................................................................... 24
13.15 INLINE QUICK RELEASE VALVE (QR-L) .......................................................................................................... 24
14. EMERGENCY DOOR OPENING VALVES ...................................................................................................... 24
14.1.1 Interior Valve Maintenance ................................................................................................................. 24
15. AIR HORN VALVE ...................................................................................................................................... 25
16. AIR SYSTEM TROUBLESHOOTING .............................................................................................................. 25
17. BRAKE OPERATION ................................................................................................................................... 25
18.
DISC BRAKES ............................................................................................................................................. 26
18.1 INSPECTION POINTS ..................................................................................................................................... 26
18.2 FUNCTIONAL AND VISUAL CHECK ................................................................................................................ 30
18.2.1 Wear Check of Pads ............................................................................................................................. 30
18.2.2 Wear Check of Disc .............................................................................................................................. 32
18.2.3 Wear Check of Pads/Disc - Drive Axle Equipped With a Rubber Bushing and Exposed Guide Pin ...... 33
18.2.4 Wear Check of Pads/Disc - Front and Tag Axle - Equipped With Visual Wear Indicator .................... 33
18.2.5 Continuous Wear Sensor option .......................................................................................................... 34
18.2.6 Checking Correct Functioning of the Adjuster / Checking That Caliper Operates Smoothly Over Its Full
Range of Movement ............................................................................................................................................ 34
18.2.7 Caliper check - Caliper Running Clearance ........................................................................................... 37
18.2.8 Caliper check - Caliper Movement Along Guide Pins ........................................................................... 37
18.2.9 Clearance Measurement Check of Bearing Variants (6) ...................................................................... 38
18.2.10 Checking Sealing Elements - Caliper Guide Pin Seals ...................................................................... 38
18.2.11 Checking Sealing Elements - Tappets and Boot Assemblies ............................................................ 39
18.3 PAD REPLACEMENT ..................................................................................................................................... 39
19. SAFE SERVICE PROCEDURES ...................................................................................................................... 40
20.
AIR BRAKE TROUBLESHOOTING ................................................................................................................ 40
21.
BRAKE AIR CHAMBER ............................................................................................................................... 42
21.1 MAINTENANCE............................................................................................................................................. 42
2 PA1621 Maintenance Manual All Series | Revised June 2020