Komatsu PC1250-11, Original Instructions Manual

Page: 338 / 452

METHOD FOR CHECKING TRACK TENSION
1.
Run the engine at low idle, then move the machine forward for a distance equal to the track length on
ground, and slowly stop the machine.
2.
Prepare the straight wooden bar (3) which has an enough
length from the second carrier roller (1) to the third carrier
roller (2). Put it onto the track shoe.
3.
Measure the maximum deflection (a) between the bottom
surface of the wooden bar and top surface of the track
shoes.
Standard deflection
Deflection (a) is correct if it is 10 to 30 mm.
If the deflection is out of the standard range, adjust it into
the standard range.
METHOD FOR ADJUSTING TRACK TENSION
k k
WARNING
Never loosen valve (1) more than 1 turn.
If valve (1) is loosened more than 1 turn, there is a danger of valve (1) flying out under the high internal
pressure of the grease.
Never loosen any part other than valve (1). Never put your face in the mounting direction of valve (1).
If the track tension cannot be loosened by the above procedure, ask your Komatsu distributor for repair.
METHOD FOR INCREASING TRACK TENSION
Items to be prepared
Grease pump
1.
Pump in grease through the valve (1) by using a grease
gun.
2.
Run the engine at low idle, move the machine slowly for-
ward (by the length of track on the ground), then stop the
machine, so that the you can check that the tension is cor-
rect.
3.
Check the track tension again, and if the tension is not cor-
rect, adjust it again.
4.
Continue to pump in grease until (A) becomes 200 mm. If
the tension is still loose, the pins and bushings are exces-
sively worn, so they must be inverted or replaced. Ask
your Komatsu distributor for repair.
MAINTENANCE PROCEDURE MAINTENANCE
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