Komatsu 830E-AC Shop Manual page 758

Disassembly
1. If removal of the hoist cylinder eye bearings is
necessary, remove retainer ring (4, Figure 8-17)
and press out bearing (5).
2. Mount the hoist cylinder in a fixture which will
allow it to be rotated 180°.
3. Position cylinder with the cover (10, Figure 8-
18) mounting eye at the top. Remove cap
screws (11) and lockwashers retaining the
cover to the housing (4).
4. Using two 0.88 in. dia. x 9 in. long, threaded cap
screws, thread them into the two threaded holes
in the cover (10). Screw the cap screws in
evenly until the cover can be removed. Lift
cover straight up until quill assembly (22) is
clear. Remove O-ring (12) and backup ring (23).
5. Remove cap screws (7) and flatwashers (5)
attaching the rod bearing retainer (6) to the rod
(1). Remove the seal (8).
6. Fabricate a retainer bar using a 6 x 25 x 460
mm (1/4" x 1" x 18") steel flat. Drill holes in the
bar to align with a pair of tapped holes spaced
180° apart in the housing. Attach bar to housing
using cap screws (11).
NOTE: A retainer bar is required to prevent the first
and second stage cylinders from dropping out when
the housing is inverted.
7. Rotate the cylinder assembly 180°, until the
lower mounting eye is at the top. Hook a lifting
device to the eye on the rod (1) and lift the rod
and third stage cylinder assembly out of cylin-
der housing. If equipped, remove cushion ring
(24).
NOTE: As internal parts are exposed, protect
machined surfaces from scratches or nicks.
8. Rotate the cylinder housing 180°. Remove the
retainer installed in step 5.
9. Fabricate a round disc 318 mm (12.5 in.) in
diameter 10 mm (0.38 in.) thick with a 14 mm
(0.56 in.) hole in the center. Align the disc over
the second (2) and first (3) stage cylinders at
the bottom of the cylinder housing.
L8-16
10. Insert a 13 mm (0.50 in.) dia. x 1320 mm (52 in.)
threaded rod through the top and through the
hole in the disc. Thread a nut on the bottom end
of the threaded rod below the disc.
11. Screw a lifting eye on the top end of the rod.
Attach it to a lifting device and lift the second
and first stage cylinders out of the housing.
12. Remove lifting tools from the second and first
stage cylinder assembly.
13. Slide the second stage cylinder (2) down inside
the first stage cylinder (3). Remove snap ring
(9) from inside the first stage cylinder.
14. Remove second stage cylinder from first stage
cylinder by sliding it out the top.
15. Remove all old bearings, O-rings, and seals
from the hoist cylinder parts.
1. Rod & Third Stage
2. Second Stage Cylinder
3. First Stage Cylinder
4. Housing
5. Plate
6. Rod Bearing Retainer
7. Cap Screw (12-point)
8. Seal
9. Snap Ring
10. Cover
11. Cap Screws
12. O-Ring
13. Bearing
14. Bearing
15. Seal
16. Seal
17. Bearing
18. Buffer Seal
19. Bearing
20. Rod Seal
21. Rod Wiper
22. Quill Assembly
23. Backup Ring
24. Ring, Cushion
Hoist Circuit Component Repair
FIGURE 8-18 HOIST CYLINDER
L08038