TM10-3930-660-20 12-7. SERVICE BRAKE CONTROL VALVE   - REPLACE/ADJUST (Cont’ d) At operating temperatures, is hot and under pressure. hydraulic oil Hot oil can cause injuries. Allow hydraulic oil to cool before disconnecting any hydraulic lines. CAUTION Wipe the area clean around all hydraulic connections to be opened during removal and disassembly. Cap oil lines and plug holes after removing lines. Contamination of the hydraulic system could result in premature failure. If more than one hydraulic line is to be removed, identify lines to assure proper installation. Use suitable container to catch any hydraulic oil that may drain from  system. 1. 2. PUMP BRAKE PEDAL TO RELIEVE ACCUMULATOR  PRESSURE. With the engine stopped, pump the brake pedal until no power assistance is felt through the pedal. This will require approximately 20 depressions of the brake pedal. DISCONNECT BRAKE PEDAL LINKAGE. From under the cab, remove cotter pin (1) and clevis pin (2) securing push rod pin (3) and clevis (4) to the brake pedal arm (5). Remove clevis (4) from brake pedal arm (5). Discard cotter  pin  (l). 12-16