Komatsu 830E-AC Shop Manual page 568

Test Set Up Procedure
1. Position the valve in the fixture to allow plung-
ers to be activated by hand using a lever (refer
to Figure 3-9).
2. Attach the pilot input supply pressure to the pilot
port labeled "PX" on the rear of the valve.
3. Attach the main supply input pressure to the O-
ring ports on the rear of the valve labeled "P1"
and "P2".
4. Attach the tank return line to the O-ring port
labeled "T" on the rear of the valve.
5. Attach the O-ring regulated output ports "B1"
and "B2" to the test lines. Pressure monitoring
devices in these two lines must be capable of
24 132 kPa (3,500 psi). Connect all ports. The
connections should be according to the diagram
shown in Figure 3-9. All ports must be used and
connected.
All ports must be used. Relieve pressure before
disconnecting hydraulic and other lines. Tighten
all connections before applying pressure.
Avoid spillage and contamination! Avoid contact
with hot oil if the machine has been operating.
The oil will be at very high 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 injury is not received
immediately.
6. Start hydraulic pump and regulate output pres-
sure to 22 064 kPa (3,200 psi) at pressure
gauge (3). Pressure gauges (7 & 10) should
read zero.
7. Set pilot supply pressure on test stand to 22
064 kPa (3,200 psi)
8. Return line pressure during this test is not to
exceed 34 kPa (5 psi).
9. Test the valve with ISO grade hydraulic oil at
49° ± 3° C (120° ± 10° F).
J3-14
Brake Valve Output Pressure Adjustment
1. Install the pedal pivot shaft pin in the actuator
base by itself without installing the pedal
assembly.
2. By taking a screw driver or pry bar and placing it
under the pivot pin and on top of the threaded
plunger assembly, each circuit can be actuated
individually. Refer to Figure 3-9.
3. Gradually apply pressure on each circuit (one at
a time) to check for leaks around the plunger.
Make sure the adjustment collar is screwed all
the way down on the threads.
4. "B1" Adjustment: Adjust the adjustment collar
up (counter-clockwise) starting with one turn
increments until the output pressure at port "B1"
is 10 894 ± 517 kPa (1,580 ± 75 psi) with the
adjustment collar contacting the actuator base
(fully actuated). Fine adjustment will require
turning the collar only in 1/8 turn increments.
5. "B2" Adjustment: Adjust the adjustment collar
up (counter-clockwise) starting with one turn
increments until the output pressure at "B2" is
20 685 -0/+1 034 kPa (3,000 -0/+150 psi) with
the adjustment collar contacting the actuator
base (fully actuated). Fine adjustment will
require turning the collar in 1/8 turn increments.
6. Tighten the setscrews in the adjustment collars
to 2.8 - 3.4 N·m (25 - 30 in. lbs) torque. The
entire plunger may have to be rotated to get to
the cap screws.
7. Check pressures again after tightening the set
screws. If the pressures have moved out of
specified range, loosen the appropriate set
screw and re-adjust.
8. Cycle each circuit 50 times using pilot apply.
This is done by closing needle valve (5) and
opening needle valve (4). Read pressure on
gauges (7 & 10). Close valve (4) and open
valve (5). The pressure gauges (7 & 10) should
indicate 0 pressure.
Brake Circuit Component Service J03034