Komatsu F30791, Shop Manual

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REMOVAL OF THE BOOM
Disconnect the negative terminalcable (±) from the
battery.
1 - Remove the arm assembly. (For details, see «RE-
MOVAL OF THE ARM ASSEMBLY»).
2 - Remove the arm cylinder. (For details, see «RE-
MOVAL OF THE ARM CYLINDER»).
3 - Remove the working beam (1).
4 - Stop the engine, and rest the boom (2) on a block «A».
5 - Stop the engine and move the PPC valve several
times to release pressures in the cylinder.
6 - Place a stand «B» beneath the cylinder (3).
7 - Remove the pin (4) and rest the cylinder on a stand.
8 - Start the engine and completely retract the piston rod
(5).
9 - Stop the engine and release the residual hydraulic
pressures. (For details, see «20. CONTROLS AND
ADJUSTMENTS»).
10 - Put a sling round the boom (2) and apply a slight ten-
sion to the cables.
11 - Disconnect the hoses (6) (N
o
. 10); plug the tubes to
prevent entry of impurities.
H Remove the wiring harness lock clips.
12 - Remove the pin (7) and remove the boom (2).
Boom: PC20R-8: 80 kg
PC27R-8: 126 kg
30-76
REMOVAL AND INSTALLATION BOOM
PC20R-8 PC27R-8
RKPA3511
2
1
RKPA3770
A
2
3
B
RKPA3522
4
5
RKPA3780
6
6
7