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Published 9-04-2014, Control # 422-08
RT765E-2 SERVICE MANUAL
SWING SYSTEM
6
GROVE
HYDRAULIC SWIVEL
Description
Each of the ports on the spool and case of the swivel is
stamped with the port number. The function of each port is
described below.
Theory Of Operation
The hydraulic swivel allows oil to flow from the pumps to
various crane functions on the superstructure. All oil is
routed into the spool portion of the swivel where, through a
series of internally drilled passages, oil is transferred to
circumferential channels on the spool exterior. These
channels correspond with a mating port on the outer case of
the swivel. Each channel is separated by a series of nylon
and O-ring seals that prevent transfer of oil and pressure.
Return flow from the crane superstructure is accomplished in
the same manner through another set of ports.
Maintenance
Removal
1.
Extend and set the outriggers. Ensure the crane is level
and the boom is over the front.
2.
Elevate the boom and note at what boom angle, you
have the most clearance between the lift cylinder and
the turntable side plate. Shut down the engine.
3.
Measure the distance from the top of the lift cylinder to
the base of the boom section where the lift cylinder
attaches. Cut two pieces of 10 x 10 cm (4 x 4 in) oak to
fit.
NOTE:
It might be necessary to raise the boom slightly to
allow installation of the blocking.
NOTE:
This blocking is to add extra support for the boom.
Any seepage or leakage in the holding valves or
internally in the cylinders will allow the boom to
settle over a period of time.
4.
Use the oak blocking to block between the barrel of the
lift cylinder and the boom base section.
5.
Tag and disconnect the hydraulic lines from the case of
the hydraulic swivel. Cap or plug all lines and openings.
6.
Tag and disconnect the hydraulic lines and water lines
from the spool of the hydraulic swivel. Cap or plug all
lines and openings.
7.
Tag and disconnect the water lines from the case of the
water swivel. Cap or plug all lines and openings.
8.
Disconnect the swivel wiring harness connectors from
the carrier receptacles and the yellow ground wire from
the connector mounting bracket on the carrier frame. If
necessary, remove the electrical swivel. Refer to
Electrical Swivel in this Section.
Port #
Test Pressure
psi (kPa)
Function
1
3625 (25,000)
Brake-Front (Primary)
2
3625 (25,000)
Brake-Rear (Secondary)
3
3625 (25,000)
4
725 (5000)
Dual Return
5
3625 (25,000)
Swing/Steer
6
4350 (30,000)
Hoist/Lift/Tele
7
3625 (25,000)
Steer, Front-Left
8
3625 (25,000)
Accum Charge Valve
9
3625 (25,000)
Steer, Front-Right
10
725 (5000)
Drain
11
A/C
12
A/C
A
---
Heater Supply (Coolant)
B
---
Heater Return (Coolant)
Reference Only