Section 8. Theory of Operation
Model 9600/9700 Swing-Reach ® Lift Truck
Hydraulic Components
Hydraulic Components Main Hydraulic Manifold The main hydraulic manifold, located in the tractor assembly, controls main and mini mast lift and lower. It also contains a relief valve used with the load handler. The following components are installed on the manifold: SOL3 (Main Load Hold) - the main mast load holding solenoid. When activated, this solenoid allows fluid to exit the main lift cylinders for lowering. SOL4 (Main Lift Select) - the main lift select solenoid. When activated, this solenoid allows fluid to enter the main lift cylinders for lifting. SOL5 (Mini Load Hold) - the mini mast load holding solenoid. When activated, this solenoid allows fluid to exit the mini lift cylinder for lowering. SOL6 (Mini Lift Select) - the mini lift select solenoid. When activated, this solenoid allows fluid to enter the mini lift cylinder for lifting. Main Lift Press - used to determine weight on main mast. Voltage output varies, depending on hydraulic system pressure. Mini Lift Press - used to determine weight on mini mast. Voltage output varies, depending on hydraulic system pressure. Load Handler Relief - used to limit pressure in the rotate/reach circuit.
Lift Pump Manifold The Lift Pump manifold, located at the bottom of the lift pump. controls fluid return to the hydraulic reservoir and pre-pressurization for optimal performance. The following components are installed on the manifold:
CV1 - used as a suction line to the pump and to correctly route return oil for lowering through CV2 to the hydraulic filter. CV2 - used to prevent oil from flowing incorrectly during lift. During lower, routes oil through the hydraulic filter. CV3 - used to allow pre-pressurization of the system to transition from a lift to lower command. Lift Relief - used to limit pressure in the main and mini mast lift circuits.
Mini Mast Manifold The Mini Mast manifold, located at the top of the Mini Mast, controls the rotate, traverse, and reach functions. Mounted into the valve body are the following components: SOL7 (Traverse PWM) - proportional valve used to control traverse speed. SOL8 (Rotate PWM) - proportional valve used to control reach and rotate speed. When activated, fluid is routed to the reach/rotate direction valve. If no current is present at the coil, the pilots open and allow oil to return to the tank. SOL9A (Traverse Dir A) - valve used to route oil from the pump to port TR2 (Right). SOL9B (Traverse Dir B) - valve used to route oil from the pump to port TR1 (Left). SOL10A (Reach/Rotate Dir A) - valve used to route oil from the pump to port R1 (CW, Retract). SOL10B (Reach/Rotate Dir B) - valve used to route oil from the pump to port R2 (CCW, Reach). Rel 3 (Relief Valve 3) - used to limit pressure in the traverse circuit.
SOL1 - allows lowering of the main or mini lift. When activated, this solenoid allows fluid to return to the reservoir.
8-12
Publication: 1089040, Issued: 08 Apr 2016
