HYDRAULIC SYSTEM
RT770E
2-46
Published 11/26/2014, Control # 447-05
HOLDING VALVE
Description
A bolt-on externally piloted manifold style holding valve is
installed on the lift cylinder and a cartridge style holding valve
is installed into each telescope cylinder port block.
Maintenance
Removal
1.
Unscrew holding valve from its port block or manifold.
Installation
1.
Check the inside of the port block or manifold for any
sharp edges or burrs and remove as necessary with
emery cloth.
2.
Install new O-rings onto the holding valve.
3.
Lubricate the holding valve and O-rings with clean
hydraulic oil.
NOTE:
The holding valve should turn by hand until
compression of the O-rings begins.
4.
Carefully install the holding valve into the port block or
manifold until fully seated.
5.
Test the holding valve and port block or manifold by
operating the lift cylinder and/or the telescope cylinder,
as applicable. Verify lift cylinder and/or telescope
cylinder works without problems; verify there is no
leaking. Make repairs as needed.
CAUTION
Do not damage the O-rings during installation of the
holding valve. If the holding valve turns freely then gets
hard to turn, then easy to turn, remove the holding valve
and check the O-rings. They have probably been
damaged by a sharp edge of a port.
Summary of Contents for Grove RT770E
Page 3: ...Service Maintenance Manual Grove RT770E ...
Page 4: ......
Page 40: ...INTRODUCTION RT770E SERVICE MANUAL 1 26 Published 11 26 2014 Control 447 05 THIS PAGE BLANK ...
Page 124: ...HYDRAULIC SYSTEM RT770E 2 84 Published 11 26 2014 Control 447 05 THIS PAGE BLANK ...
Page 149: ...4 5 Published 11 26 2014 Control 447 05 RT770E SERVICE MANUAL BOOM 4 GROVE FIGURE 4 2 ...
Page 150: ...BOOM RT770E SERVICE MANUAL 4 6 Published 11 26 2014 Control 447 05 FIGURE 4 2 continued ...
Page 152: ...BOOM RT770E SERVICE MANUAL 4 8 Published 11 26 2014 Control 447 05 FIGURE 4 2 continued ...
Page 154: ...BOOM RT770E SERVICE MANUAL 4 10 Published 11 26 2014 Control 447 05 FIGURE 4 2 continued ...
Page 224: ...5 24 Published 11 26 2014 Control 447 05 HOIST AND COUNTERWEIGHT RT770E This Page Blank ...
Page 276: ...POWER TRAIN RT770E 7 30 Published 11 26 2014 Control 447 05 THIS PAGE BLANK ...
Page 300: ...UNDERCARRIAGE RT770E 8 24 Published 11 26 2014 Control 447 05 FIGURE 8 28 ...
Page 348: ...LUBRICATION RT770E 9 36 Published 11 26 2014 Control 447 05 FIGURE 9 14 102 8130 2 ...
Page 356: ......
Page 357: ......