TM10-3930-660-20 18-32. BOOM HOIST CYLINDERS - REPLACE (Cont't) NOTE If removing both cylinders (2) at the same time, note that one cylinder (2) will fully retract before other cylinder (2) begins to retract. Have assistant signal operator when both cylinders (2) are fully retracted. 6. 7. 8. 9. 10. 11. 12. START ENGINE AND RUN AT FULL THROTTLE,  TM10-3930-660-10. USING BOOM HOIST JOYSTICK CONTROL VALVE, FULLY RETRACT CYLINDER (2). STOP ENGINE, TM10-3930-660-10. CAREFULLY LOWER CYLINDER (2), USING LIFTING DEVICE, UNTIL CYLINDER (2) IS RESTING ON BOARD PLACED ON MAIN DECK  . TAG AND DISCONNECT HYDRAULIC LINES (5 AND 6) FROM CYLINDER PORTS. REMOVE BOOM HOIST CYLINDER LOWER PIVOT  PIN  (7). a. b. Remove locknut (8) and screw (9). Discard locknut. Remove lower pivot pin (7), using suitable pin puller. MOVE LIFTING DEVICE TO CYLINDER’S BALANCE POINT AND CAREFULLY LIFT CYLINDER (2) OFF OF VEHICLE. INSTALLATION NOTE Remove caps and plugs as hoses are installed. Wipe all sealing surfaces on cylinder and hoses CAREFULLY  LOWER BOARD PLACED ON LIFTING DEVICE. clean  and  dry. CYLINDER (2) ONTO MAIN DECK USING 18-129