Shock & Suction Valves - Komatsu 830E Shop Manual

SHOCK & SUCTION VALVES
Shock & Suction Valve Settings
Relieve pressure before disconnecting hydraulic
lines. Tighten all connections securely before
applying pressure.
Hydraulic fluid escaping under pressure can
have sufficient force to enter a person's body by
penetrating the skin and cause serious injury and
possibly death if proper medical treatment by a
physician familiar with this type of injury is not
received immediately.
Be sure accumulator oil pressure has been bled
down. Turn steering wheel; the wheels should
not move if oil pressure has been relieved.
1. Shut down engine, turn keyswitch "Off" and
allow accumulator to completely bleed down
before opening circuits to take measurements,
to make repairs, or to install or remove gauges.
2. Install a calibrated 5000 psi (35,000 kPa) gauge
on one of the two diagnostic ports located on
the steering cylinder manifold located just below
the engine.
3. Prior to checking the shock & suction valves in
the flow amplifier, raise the steering relief pres-
sure.
a. Remove steering relief valve external plug
using an 8 mm metric allen wrench. Refer to
Figure 10-3.
b. Gently bottom out the steering relief valve
using a 5 mm metric allen wrench. Refer to
Figure 10-3 for relief valve location.
FIGURE 10-2. FLOW AMPLIFIER VALVE
L10016 05/03
FIGURE 10-3. FLOW AMPLIFIER VALVE
4. Check flow amplifier shock & suction valve pres-
sure. Pressure check can be accomplished by
steering away from steering cylinder stops, then
steering into stop and continue to turn steering
wheel. Gauge should read 2900 psi (19,996
kPa). Move the gauge connection to the other
diagnostic port to test the pressure of the other
valve. If shock & suction valve pressure is not
correct, replace valves.
NOTE: The shock & suction valves are only serviced
as complete units, and cannot be adjusted while
installed in the flow amplifier valve.
5. After checking shock & suction valves, lower the
steering relief pressure to 2500 psi (17,237
kPa). Steering relief pressure can be adjusted
by steering full left or right and adjusting steer-
ing pressure at the flow amplifier while holding
slight pressure on the steering wheel. Replace
the external steering relief valve plug.
6. Remove test equipment and reconnect all lines
and hoses to the proper location.
Hydraulic Check-out Procedure L10-3