Komatsu PC20R-8, Operation & Maintenance Manual

Page: 141 / 196

MAINTENANCE PLAN
139
ADJUSTMENT
DANGER
•
The grease contained in the hydraulic cylinder is under
pressure. For this reason, do not loosen the greasing
valve (1) giving it more than one turn; if the valve is loos-
ened excessively, it may be pushed out due to the grease
pressure and this is very dangerous for the operator.
Do not loosen any other component apart from the valve
(1).
•
If you notice excessive resistance while injecting grease,
slowly move the machine forward and backward for a
short distance.
To increase the tension
1 - Carefully clean the greasing valve (1) and inject grease
through the greaser (2) until reaching the desired tension.
2 - When, owing to the injection of grease, the idler shoe reach-
es the “S” measure, that is, 0 mm and the track tension is not
sufficient, this means that the pins and bushings are exces-
sively worn.
It is therefore necessary to turn or change the pins and bush-
ings.
For any change or repair, contact your Komatsu Utility Deal-
er.
To reduce the tension
1 - Gradually loosen the greasing valve (1) to let the grease out;
do not give the valve more than one turn.
Use a 19 mm hexagon spanner.
2 - If the grease does not flow out freely, move the machine
slowly forward and backward for a short distance.
3 - Tighten the valve and remove any trace of grease.
4 - Move the machine forward and backward and, after stopping
it, check the track tension again.
IMPORTANT
☞
•
The wear of pins and bushings varies according to the
work conditions and the characteristics of the ground on
which the machine operates.
Therefore, it is necessary to check the track tension fre-
quently.
•
When working on rocky or extremely uneven ground, in-
crease the track tension in order to prevent the introduc-
tion of stones or rubble between the tracks and the
sprocket; when working on soft or muddy ground, de-
crease the track tension, since the soil penetrates be-
tween rollers, sprocket and tracks and tends to increase
it.
RWA09320
2
1
RWA06550
S