Front Suspension; Removal - Komatsu 830E Shop Manual

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The HYDRAIR II suspensions are hydro-pneumatic
components containing oil and nitrogen gas. The oil
and gas in the four suspensions carry the gross truck
weight less wheels, spindles and final drive assembly.
The front suspension cylinders consist of two basic
components; a suspension housing attached to the
truck frame and a suspension rod attached to the front
spindle. Check valves and orifice dampening holes
control suspension travel to provide good ride qualities
on haul roads under loaded and empty conditions. The
front suspension rods also act as kingpins for steering
the truck.
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The HYDRAIR II suspension cylinder requires only
normal care when handling as a unit. However, after
being disassembled these parts must be handled care-
fully to prevent damage to the machined surfaces. Sur-
faces are machined to extremely close tolerances and
are precisely fitted. All parts must be completely clean
during assembly.

Removal

1. Park unloaded truck on hard level surface. Block
wheels and apply parking brake. Remove front
wheel and tire according to "Removal" instruc-
tions in Section "G", Front Tire and Rim. Remove
front wheel hub and spindle as covered in Section
"G".
2. Remove boot clamp and boot from around sus-
pension. Disconnect pressure sensor.
3. Discharge nitrogen pressure from suspension by
removing cap from charging valve (5, Figure 2-1).
Turn the charging valve swivel nut (small hex) (3,
Figure 2-2) counterclockwise 3 full turns to
unseat valve seal (DO NOT turn more than three
turns). DO NOT TURN LARGE HEX (4) (see
DANGER below). Wearing face mask or goggles,
depress valve stem until all nitrogen pressure has
been relieved.
Make certain only the swivel nut (3) turns. Turning
the complete charging valve assembly may result
in the valve assembly being forced out of the sus-
pension by the gas pressure inside.
H02016

FRONT SUSPENSION

1. Cap Structure
2. Sensor Port Plug
3. Charging Valve Guard
4. After all nitrogen pressure has been relieved,
loosen large hex (4) and remove charging valve
assembly. Discard flat gasket under large hex.
FIGURE 2-2. CHARGING VALVE INSTALLATION
1. Valve Guard
2. Valve Cap
5. Place a suitable container under suspension cyl-
inder. Remove bottom drain plug and allow cylin-
der to drain completely.
NOTE: Front HYDRAIR
with lower bearing retainer puller holes. If only rod
wiper, rod seals, bearing, O-ring and backup ring
replacement is required, it will not be necessary to
remove suspension from truck. Refer to "Minor Repair
Only (Lower Bearing Structure & Seals)" for bearing
structure removal and installation.
Front Suspensions
FIGURE 2-1. SUSPENSION CAP
4. Vent Plug
5. Nitrogen Charging
Valve
3. Swivel Nut (Small Hex)
4. Valve Body (Large
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II suspensions are equipped
H2-1