Komatsu 830E-AC Shop Manual page 561

DISASSEMBLY
NOTE: If equipped with, and not already removed,
remove electronic retard pedal (16, Figure 3-3) from
brake pedal by removing pivot shaft (8). The rebuild
and adjustment procedures for the brake valve (1)
are the same, whether or not the brake pedal has the
retard pedal assembly attached to it.
NOTE: During disassembly, precision machined
parts should be ink marked or tagged to ensure
proper reassembly and minimize adjustment time. All
items must be placed back into the bores from which
they were removed.
1. Match mark each section of the brake valve
prior to disassembly.
2. Drain all oil from all ports of the valve by rotating
the valve over a suitable container.
3. Secure brake valve in upright position in a vice.
4. Remove the brake pedal actuator (7, Figure 3-
2) by removing the retaining clips (2), then
remove the pivot shaft (3) with a punch and
hammer.
FIGURE 3-4. ACTUATOR CAP & BOOT
1. Actuator Cap
2. Boot
3. Cap Screw
4. Retainer Plate
J03034
5. Cap Screw
6. Actuator Base
7. Threaded Insert
Brake Circuit Component Service
5. Remove the four button head allen screws (3,
Figure 3-4) securing the boot retainer plate (4).
6. Remove the boot retainer plate (4), boot (2),
and actuator cap (1) as an assembly by grasp-
ing the boot and gently lifting from the valve
body.
7. Remove cap screws (31, Figure 3-5) and plate
(30).
8. Remove and discard the O-ring (22) and face
seal (23).
9. Loosen plunger locknuts (2). Loosen the socket
head cap screw from the adjustment collars (1).
10. Unscrew and remove the adjustment collars.
11. Remove the two socket head cap screws (5,
Figure 3-4) that retain the actuator base (6) to
the valve body.
12. Remove the actuator base from the valve body.
13. Remove controller from vice.
14. Remove the four cap screws (29, Figure 3-5)
and washers (28) from the base of the valve.
15. Remove base plate (27).
16. With the valve upright, retaining plug (26)
should fall out. If the plug does not fall out,
lightly tap to dislodge the plug.
NOTE: The spools (8), reaction plungers (16, 17) and
spool return springs (15) may fall out at this time.
Keep parts separate so they may be installed in the
same bores from which they were removed. The "B1"
reaction plunger (16) is larger than the "B2" reaction
plunger (17).
17. Remove and discard the O-ring (25) from the
counterbore in the base of the valve body.
18. With the controller upright on the work bench,
hold the valve with one hand and push the "B1"
actuator plunger (2) down with the other hand
until the regulator sleeve (14) becomes loose.
19. Repeat the above procedure to loosen the "B2"
regulator sleeve.
20. Turn the valve on its side on the work bench
and remove both regulator sleeves (14) from
the valve body.
J3-7