Komatsu 930E-2, Shop Manual

Page: 286 / 739

Disassembly
NOTE: The suspension should be placed in a fixture
which will allow it to be rotated 180° vertically.
1. Depress charging valve stem to insure all nitrogen
gas pressure has been released prior to removing
charging valve. Wear face mask or goggles while
relieving nitrogen gas.
2. Remove charging valve cover. Remove charging
valve (12, Figure 3-4). Remove and discard
charging valve O-ring. Remove vent plug (14).
3. Place the suspension in a vertical position (piston
rod down). Suspension will contain oil which will
drain through the vent port. Remove piston pro-
tection shields (8), if installed.
4. Rotate the suspension 180°. Remove socket head
capscrews (18) and pull suspension piston as-
sembly (5) from housing (1). The housing bearing
(21) will be removed with the piston assembly.
5. Remove capscrew and hardened washers (2 &
3). Remove piston bearing (4) from piston rod.
Remove ball checks (22) from piston. Slide the
housing bearing (21) off of the piston.
6. Remove and discard wiper seal (15), rod seal (16),
step seal (17), O-ring (20), and backup ring (19)
from housing bearing.
7. Remove vent plug (7).
8. If the spherical bearings (6, Figure 3-3) require
replacement, remove the retainer rings (5). Press
bearing out of bore.
Cleaning and Inspection
1. Clean all parts thoroughly in fresh cleaning sol-
vent. Use a solvent that does not leave a film after
evaporation, such as Trichlorethylene, Acetone
or Laquer Thinner.
When using cleaning agents follow the solvent
manufacturer’s instructions.
2. Dry all parts completely using only dry, filtered
compressed air and lint free wiping materials.
3. Inspect all parts for evidence of wear or damage.
Inspect plated surfaces for scratches, nicks or
other defects. Replace or repair any damaged
parts.
NOTE: If other repairs are necessary, refer to your
local Komatsu Distributor for repair information and
instructions not covered in this manual.
Assembly
Assembly must be accomplished in a clean, dust free
work area. All parts must be completely clean, dry and
free of rust or scale. Lubricate all interior parts and
bores with fresh suspension oil. (See Oil Specifications
under “Oiling and Charging Procedure”, this section).
1. Install the spherical bearing (6, Figure 3-3) in the
eye of the piston rod and of the cylinder housing.
2. Place the ring retainers (5) in position to secure
the bearings.
3. Install the piston rod vent plug (7, Figure 3-4).
4. Install the wiper seal (15), rod seal (16), and step
seal (17). When installing backup rings with
rod seal (16) and step seal (17), be certain
radius is positioned toward the seal and the
white dot is positioned away from the seal as
shown in Figure 3-4.
5. Install O-ring (20) and backup ring (19) on the
bearing (21). Backup rings must be positioned
toward the flange of the bearing.
6. Slide the bearing (21) onto the lubricated piston
rod (5).
7. Place the ball checks (22) in the piston and install
the piston rod bearing (4) with the capscrews and
hardened washers (2 & 3). Tighten the capscrews
to standard torque.
8. With the lubricated housing (1) held in a vertical
position, slide the piston assembly part way into
the housing. Slide the loose housing bearing
down onto the housing and fasten with socket
head capscrews (18). Tighten the capscrews to
standard torque. Use care during piston installa-
tion to prevent damage to machined and chrome
surfaces.
9. Install vent plugs (11 & 14). Install shield (8).
NOTE: If suspension is to be stored, put in two pints
(1.0 l) of a rust preventive oil. This oil must be drained
when suspension is put into service.
10. Using new O-ring, install charging valve. Tighten
large hex of charging valve to 16.5 ft.lbs. (22.4
N.m) torque.
H3-4 Rear Suspensions H03013