JLG 600SC_660SJC Service Manual - Manual (Page 95)

SECTION 5 - CAT CHASSIS (S/N 0300128000 TO PRESENT)
3121157 – JLG Lift – 5-3
REFRAIN FROM EXERTING AXIAL LOAD. IF AXIAL LOAD IS
EXERTED, PLEASE CONTACT US.
EXERTION OF AXIAL LOAD MAY CAUSE EARLY WEAR OF THE
INSIDE OF THE REDUCTION GEAR.
Use of Parking Brake
RELEASE THE PARKING BRAKE TO OPERATE THE MOTOR.
IF THE MOTOR IS OPERATED WITH THE PARKING BRAKE ENGAGED,
A DISK FOR THE PARKING BRAKE MAY WEAR QUICKLY, RESULTING
IN THE PARKING BRAKE FAILURE. A PARKING BRAKE FAILURE
WILL LEAD TO A DROP OF LIFTED LOAD OR RUNAWAY, WHICH IS
VERY DANGEROUS.
DO NOT USE THE PARKING BRAKE FOR CONTROLLING ROTATION
OF THE MOTOR.
EARLY BREAKAGE OF THE DISK FOR THE PARKING BRAKE LEADS
TO A PARKING BRAKE FAILURE. AS A RESULT, LIFTED LOAD MAY
DROP, WHICH IS VERY DANGEROUS.
EXCESSIVE TORQUE EXERTED ON THE MOTOR SHAFT AND DRIVE
GEAR SHAFT OF THE REDUCTION GEAR WILL CAUSE BREAKAGE OF
THE MOTOR SHAFT AND DRIVE GEAR SHAFT OF THE REDUCTION
GEAR. THE RESULT WILL LEAD TO A DROP OF LIFTED LOAD DUR-
ING OPERATION, WHICH IS VERY DANGEROUS.
WHEN STOPPING THE MOTOR, BE SURE TO APPLY THE PARKING
BRAKE.
FAILURE TO DO SO IS VERY DANGEROUS BECAUSE LIFTED LOAD
MAY DROP OR MOTOR MAY RUNAWAY.
Prevention of Overrun
DEPENDING ON THE PIPING VOLUME FROM HYDRAULIC SUPPLY
TO THE HYDRAULIC MOTOR, AND PROPERTY OF THE COUNTER
BALANCE VALVE, THE HYDRAULIC MOTOR MAY OVERRUN,
RESULTING IN EARLY BREAKAGE OF THE HYDRAULIC MOTOR.
THEREFORE, PREVENT THE MOTOR FROM OVERRUNNING FOR
PROTECTION OF THE EQUIPMENT AND USE FOR AN EXTENDED
PERIOD OF TIME (ESPECIALLY DURING WINDING DOWN). IF
OCCURRENCE OF OVERRUN CANNOT BE FULLY PREVENTED,
ADJUST SO THAT THE MAXIMUM ROTATION SPEED OF THE MOTOR
WHEN OVERRUN OCCURS BECOMES WITHIN THE ROTATION
SPEED RANGE OF THE EQUIPMENT SPECIFICATIONS.
Setting of Self-Priming Circuit
LEAKS FROM THE HYDRAULIC MOTOR AND COUNTER BALANCE
VALVE MAY CAUSE AERATION IN THE HYDRAULIC MOTOR CIR-
CUIT, LEADING TO CAVITATION AND TRAVEL MOVEMENT OF THE
HYDRAULIC MOTOR. INSTALLATION OF A SELF-PRIMING CIRCUIT
IS NECESSARY TO PREVENT CAVITATION AND TRAVEL MOVEMENT
OF THE HYDRAULIC MOTOR.
ESPECIALLY AFTER A LONG PERIOD OF QUIESCENT OPERATION, IT
IS ESSENTIAL TO FILL THE HYDRAULIC MOTOR CIRCUIT WITH
HYDRAULIC FLUID BEFORE OPERATING A WINCH.
THUS, INSTALL THE SELF-PRIMING CIRCUIT, CONSIDERING LOCA-
TION RELATIONSHIP BETWEEN THE HYDRAULIC MOTOR AND THE
OIL LEVEL OF THE HYDRAULIC PRESSURE TANK. EXERT PRES-
SURE OF 0.3 TO 0.5 MPA ON THE SELF-PRIMING CIRCUIT TO PRE-
VENT CAVITATION DURING HALTS OF MOTOR ROTATION.
IF THE HYDRAULIC MOTOR IS POSITIONED LOWER THAN THE OIL
LEVEL OF THE HYDRAULIC PRESSURE TANK, AND THE CONTROL
VALVE OPERATES FROM A TO B, AND TO T OPEN, NO INSTALLA-
TION OF THE SELF-PRIMING CIRCUIT IS NECESSARY IN PRINCIPLE.
Cases of Hydraulic Circuit
SET THE BACK PRESSURE VALUE SO THAT NO CAVITATION
OCCURS.
IF THE HYDRAULIC MOTOR IS POSITIONED HIGHER THAN THE OIL
LEVEL IN THE HYDRAULIC TANK, FILL THE HYDRAULIC MOTOR
CIRCUIT WITH HYDRAULIC FLUID BEFORE OPERATING THE
HYDRAULIC MOTOR.
PROVIDE THE SELF-PRIMING CIRCUIT.
PLEASE CONTACT US IF ANY CIRCUIT OTHER THAN THE ONES
DESCRIBED IN ATTACHED PAPERS IS USED.