Boom Extension Cylinder - Genie GTH-636 Service Manual

June 2007
REV C
1-4

Boom Extension Cylinder

How to Remove the
Extension Cylinder
Note: When removing a hose assembly or fitting,
the O-ring on the fitting and/or hose end must be
replaced and then torqued to specification during
installation. Refer to Section 2, Hydraulic Hose and
Fitting Torque Specifications.
1 Raise the boom to a horizontal position.
2 Extend the boom approximately 1 foot / 30 cm.
3 Attach a lifting strap from an overhead crane to
the extension cylinder. Support the cylinder. Do
not apply any lifting pressure.
a c
b
e
f
a boom tube number 3
b boom tube number 2
c boom tube number 1
d extension cylinder retaining pin
e extension cylinder support loop
f extension cylinder rod end nut
4 Remove the nut securing the rod end of the
extension cylinder to the number 2 boom tube.
5 Remove the extension cylinder support loop
from the number 3 boom tube.
Part No. 97487 GTH-636 • GTH-644 • GTH-842 • GTH-844 • GTH-1048 • GTH-1056
6 Place a wooden block, which measures
approximately 2 x 4 x 12 inches / 5 x 10 x 30
cm, onto the top of the number 2 boom tube in
a way that will prevent the number 2 boom tube
from retracting into the number 1 boom tube.
7 Retract the extension cylinder to the stowed
position. Turn the machine off.
8 Tag, disconnect and plug the hydraulic hoses
from the extension cylinder manifolds. Cap the
fittings on the manifolds.
d
9 Remove the fasteners securing the extension
cylinder barrel end pivot pin to the boom.
10 Use a soft metal drift to remove the pivot pin.
Remove the cylinder from the machine.
Section 4 • Repair Procedures
BOOM COMPONENTS
Crushing hazard. The extension
cylinder will fall if not properly
supported when the cylinder is
retracted.
Bodily injury hazard. Spraying
hydraulic oil can penetrate and
burn skin. Loosen hydraulic
connections very slowly to allow
the oil pressure to dissipate
gradually. Do not allow oil to
squirt or spray.
Component damage hazard.
Hoses can be damaged if they are
kinked or pinched.
Crushing hazard. The extension
cylinder will fall if not properly
supported when the pivot pin is
removed from the machine.
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