Spring Recoil And Thrust Cylinder Groups; Disassembly; Assembly - Komatsu PC20R-8 Shop Manual

REMOVAL AND INSTALLATION
DISASSEMBLY AND ASSEMBLY OF THE SPRING RECOIL AND
THRUST CYLINDER GROUPS
1 - Spring recoil group

Disassembly

1 - Place the group (1) beneath a press on which the tool
B1 is mounted.
The spring is mounted with a strong pre-loading.
Make sure that the group is well-centred and that it
is standing perfectly flat.
2 - Increase pressure slowly and compress the spring
(2).
3 - Maintaining pressure, remove the cotter pin (3) and
the nut (4).
4 - Slowly release pressure until the spring is completely
released.
H Length of released spring: 248 mm
5 - In sequence remove the tic-rod (5), the spring (2) and
the plate (6).

Assembly

To re-assemble, reverse the dismantling procedure.
.
H Tighten the nut (4) up to the indicated length of the
spring. (See «40. STANDARD MAINTENANCE»).
Mount the cotter pin (3).
H After assembly, check that the parallelism error be-
tween the faces A and B is less than 0.5 mm.
2 - Thrust cylinder
Disassembly
1 - Take out plate (8), valve 89) and nipple (10) from cy-
linder (7).
2 - Take out the piston (11) out of the cylinder.
3 - Take out the snap ring (12), the gasket (13), the
spacer (14), the anti-extrusion ring (15), and the O-
ring (16).
Assembly
. To re-assemble, reverse the dismantling procedure.
30-54

SPRING RECOIL AND THRUST CYLINDER GROUPS

B1
5
A
7
F
6
2
=
=
11
13
15
16
14
8
9
10
PC20R-8 PC27R-8
2
1
RKP06480
3
4
RKP06240
B
RKP06490
12
RKP06250