TM10-3930-660-20 12-7. SERVICE BRAKE CONTROL VALVE - REPLACE/ADJUST This task covers: a. Removal b. Installation c. Adjust Accumulator Charging Pressure Initial Setup Tools Materials/Parts Tool Kit, Automotive Mechanics Container Cotter  Pin  (1) Equipment Condition Hydraulic Oil, (App. C, Item 36) Vehicle parked on level ground. Lockwashers  (20) Wheels blocked. Loctite 242 (App. C, Item 39) Brake hydraulic pressure switch Tags (APP. C, Item 51) disconnected, para. 8-18. Hydraulic oil drained from fuel/ hydraulic tank, para. 5-10. Hydraulic oil in the system can be under pressures over 3000 psi with the engine OFF . ALWAYS relieve pressure in hydraulic lines before attempting to remove any component in the hydraulic system. With engine OFF, starter switch in RUN position, and MLRS attachment on the ground, move control levers through all operating positions several times to relieve line pressure. Relieve pressure in hydraulic oil tank by loosening filler cap very slowly. Failure to follow these precautions could result in serious personal injury. 12-15