SUBSECTION 5D
HYDRAULIC COMPONENTS
REPAIRS. The swivel is considered non-repairable. If the
1. Generously coat all parts to be assembled with hydrau-
swivel is faulty the complete swivel should be removed and
lic oil.
replaced.
2. Install the inner seal, larger diameter back-up ring, O-
REMOVAL. To remove the swivel, proceed as follows:
ring, small diameter back-up ring, and outer seal.
1. See General Removal at the beginning of this section.
NOTE
2. Disconnect the hydraulic line at the swivel and position
Cylinders (38U34 & 38U104) have a metal and rub-
the line to avoid interference as the swivel is removed. Cap
ber outer seal. Cylinders (38U39, 38U45 and
the line to prevent the entry of contaminants.
38U112) have a rubber outer seal.
3. Remove the swivel by backing it out of the shaft.
3. Install the spring and piston in the cylinder body.
INSTALLATION. To install the swivel, proceed as follows:
1. Install the O-ring on the swivel. Thread and tighten the
INSTALLATION. To install the actuating cylinder, proceed
swivel into the shaft.
as follows:
2 Remove the protective cap and connect the hydraulic
1. Secure the cylinder to the operating mechanism with the
line to the swivel.
lockwasher and capscrew.
3. Connect the battery cable. Start the engine and operate
2. Attach the linkage to the yoke or eyebolt end of the cyl-
the controls. Observe the swivel for leaks or other defects.
inder.
BRAKE, CLUTCH, AND PAWL CYLINDERS
3. Remove the dust cap from the cylinder and remove the
(38U34, 38U39, 38U45, 38U104 & 38U112)
cap from the hydraulic line. Connect the hydraulic line to
the cylinder.
REMOVAL. To remove the actuating cylinder, proceed as
follows:
4. Bleed the hydraulic cylinder to remove any air trapped in
the hydraulic line. See Bleeding Procedure in this section to
1. See General Removal at the beginning of this section.
bleed the cylinder.
2. Disconnect the hydraulic line to the cylinder. Cap the line
5. Connect the battery cable. Start the engine and operate
and install a dust cap in the cylinder to prevent the entry of
the controls. Observe the cylinder for leaks, binding or other
defects.
3. Relieve any tension on the brake, clutch or pawl oper-
ating mechanism springs. Remove the linkage from the
CRAWLER EXTENSION/RETRACTION
yoke or eyebolt end of the cylinder.
CYLINDER (38U113)
NOTE
DESCRIPTION. This cylinder is a double acting hydraulic de-
vice for extending and retracting the crawler side frame. It
See the particular brake, clutch or pawl instructions
has a 4 inch bore, 27 inch stroke and extends to a total
on how to relieve spring tension in the operating
length of 67 inches. Although this cylinder gets moderate
mechanism and how to remove the linkage from the
use, it may in time develope leaks or function erratically
yoke or eyebolt.
calling for special maintenance to be done. A special seal kit
4. Remove the capscrew and lockwasher securing the cyl-
is available and must be installed if the cylinder is over-
inder to the operating mechanism.
hauled.
REMOVAL. To remove the crawler extension cylinder, pro-
DISASSEMBLY. Use the following procedure to disassem-
ceed as follows:
ble the cylinder (see Figure 5D-5):
1. Perform the GENERAL REMOVAL procedures, as they
1. Remove the piston and spring from the cylinder body.
apply to this function, found in the beginning of this sub-
2. Remove the seals, back-up rings, and the O-ring from
section.
the cylinder body. Note the position of the seals when
2. Remove hydraulic lines at quick disconnect and pull the
removing them.
pins at either end of the cylinder. Connect the quick discon-
nects to keep them clean.
INSPECTION AND REPAIRS. Inspect the piston and cylin-
der bore for excessive wear, nicks or scratches. If either of
3. Move the cylinder to a clean, dust free work area for dis-
these parts are damaged, the entire cylinder must be re-
assembly.
paired.
DISASSEMBLY. To disassemble the cylinder, proceed as
NOTE
follows (see Figure 5D-6):
A service kit is available. See the Replacement Parts
1. Remove the two capscrews holding head gland (06)
Manual.
against lock wire (03).
ASSEMBLY. To assemble the cylinder, proceed as follows
2. Push the head gland into the body approximately 1 inch
(see Figure 5D-5):
and remove the lock wire from the groove.
5D-8
