Cross Axle Differential Lock Valve; Description; Maintenance; Check Valves - Manitowoc Grove RT9130E-2 Service And Maintenance Manual

HYDRAULIC SYSTEM
Installation
1. Position the valve to the frame and secure with the nuts
and washers.
2. Connect the electrical lines to the valve as tagged during
removal.
3. Connect the hydraulic lines to the valve as tagged during
removal.
4. Operate the applicable system and check the valve for
proper operation and any leaks.

CROSS AXLE DIFFERENTIAL LOCK VALVE

Description

The cross axle differential lock valve is located on the right
side of the rear frame. The valve is a three-way, two position
solenoid valve. The valve is used to control the application of
the crane's hydraulically applied and released cross axle
differential lock actuators.
Positioning the Axle Diff switch to LOCK shifts the three-way,
two-position solenoid valve so hydraulic oil can flow to the
engage port of the cross axle differential lock actuators,
extending them. When the actuators extend, they engage
the splines on the differential case and the axle shafts to lock
the differential assemblies together.
Positioning the Axle Diff switch to UNLOCK shifts the three-
way, two-position solenoid valve so hydraulic oil can flow to
the disengage port of the actuators, retracting them. As the
actuators retract, they unlock the axles.

Maintenance

Removal
1. Tag and disconnect the electrical connector from the
valve.
2. Tag and disconnect the hydraulic lines attached to the
valve. Cap or plug lines and ports.
3. Remove the capscrews, flatwashers and nuts securing
the valve to the frame. Remove the valve.
Installation
1. Secure the valve to the frame with the capscrews,
flatwashers and nuts.
2. Connect the hydraulic lines to the valve as tagged during
removal.
3. Connect the electrical connector to the valve as tagged
during removal.
2-54
4. Apply and release the cross axle differential lock several
times. Verify the cross axle differential lock holds the
axle from moving when applied so there is no differential
action between the wheels.
5. Check for leaks. Make repairs as needed.

CHECK VALVES

Description

There are five check valves utilized in the crane hydraulic
system. The check valves are used to block flow in one
direction and allow free flow in the opposite direction.
The crane's hydraulic dual return circuit has an in-line
plumbed check valve in one of the two return lines. It is used
to force hot return oil in the other return line to the hydraulic
oil cooler.
The swing/steer directional control valve has a check valve
installed in its outlet port to ensure there will be enough
pressure to force oil through the port anti-void check valves
for motor over run when the directional control valve is
centered.
There is an in-line mounted check valve between the
secondary ports of pump No. 1 and No. 3. It is used to boost
flow to the outrigger circuit.
The counterweight removal/cab tilt directional control valve
utilizes a check valve in its load sense line from the hoist/
telescope/boom lift directional control valve. It blocks the
load sense signal from the hoist/telescope/boom lift
directional control valve from bleeding through the
counterweight removal/cab tilt directional control valve's load
sense bleed.
There is an inlet plumbed checked valve on the front steer
control valve. It prevents steering wheel kick-back if the steer
cylinder pressure rises above the inlet port pressure.

Maintenance

Removal
1. Tag and disconnect the hydraulic lines from the valve.
Cap or plug the lines and ports.
Installation
1. Connect the hydraulic lines to the ports on the valve as
tagged during removal.
2. Verify proper operation of the valve. Check hydraulic
connections for leaks.
Published 11-22-2016, Control # 345-12
RT9130E-2 SERVICE MANUAL