Manitowoc Grove GRT9165, Service Manual

Page: 73 / 302

2-31
GROVE
GRT9165 SERVICE MANUAL HYDRAULIC SYSTEM
2
Published 10-01-2020 Control # 699-00
Bleed Off Valve
NOTE: Make sure the outrigger box pressure bleed off
valve is shut before checking the cut-off and
differential settings. For more information, see the
Operator Manual .
The pressure bleed-off valve (Figure 2-12) is used to
manually drain to reservoir any trapped pressure from
behind the outrigger box removal quick disconnects or the
telescope boom removal quick disconnects.
The in-line plumbed pressure bleed-off valve consists of a
knob adjustable flow control valve and a shuttle valve. The
a d j u s ta b l e fl o w c on tr ol v al v e k no b ca n b e tu r ne d
counterclockwise to open or clockwise to close. Full
adjustment is five turns of the knob. The shuttle valve acts as
a directional selector, allowing only the pressurized circuit to
open to the flow control drain valve.
Whenever possible, the bleed adapter should be mounted at
the highest point within the hydraulic system. The trapped air
can be relieved while the system is running at low pressure.
To bleed, loosen the bleed screw 1/2 turn counterclockwise.
After the hydraulic fluid begins to run freely from the bleed
screw, the bleed screw should be re-tightened.
Removal
1. Tag and disconnect hydraulic lines from valve. Cap or
plug all openings.
2. Remove the capscrews and washers securing the valve.
Remove the valve.
Installation
1. Install the valve and secure with the capscrews and
washers. Torque capscrews to recommended torque.
2. Connect the hydraulic lines to the valve as tagged during
removal.
WARNING
When bleeding hydraulic fluid, operate the system below
500 psi. To avoid injury, ensure that all persons are clear
of the path of discharge. Another recommended practice
is to attach a section of hose over the bleed screw/
adapter to direct oil away from the area and to reduce oil
spillage.
FIGURE 2-12
7501-2
7501
2
1
5
1
5
3
4
2
4
3
Bleed Off Valve
1 Tank Port — T
2 To Outrigger Extend Port “B”
3 To Outrigger Retract Port “A”
4 Shuttle Valve
5 Adjustable Flow Control Valve