Page 18
65-J Desel - Servce & Parts Manual
February 2021
Hydraulic System – General
The hydraulic system is designed to control all or part of machine functions by integrating various
hydraulic cartridge valves into three manifolds to provide directional, pressure, flow, and load control.
The hydraulic system is a feedback, load-sensing type. Hydraulic fluid is provided by a variable
displacement, axial piston-type Drive Pump coupled to the engine and a fixed displacement gear-type
Functions Pump mounted to the back of the piston pump. As the engine turns, the hydraulic pumps
draw fluid from the reservoir and pump this fluid to the wheel motors and valve manifolds.
Each function has a maximum pressure control limit set by pressure relief valves.
ART_4884
Jib Cylinder
Wheel Motor
(each wheel)
Platform Level Cylinder
Boom Extend Cylinder
Upper Boom Lift
Cylinder
Lower Boom Lift
Cylinder
Platform Functions
Manifold
Platform Rotator
Hydraulic
Reservoir
Functions
Manifold
Turntable
Rotator
Rotary
Manifold
Charge Filter Assembly
Drive Pump
Functions Pump
Brake/Axle/2-Speed Manifold
Auxiliary Power Unit
Axle Cylinder (2)
Steer Cylinder (2)
Secton 10 - Hydraulc System
Hydraulic System – General