Check And Adjust Track Tension - Komatsu PC450-8 Operation & Maintenance Manual

MAINTENANCE

CHECK AND ADJUST TRACK TENSION

Wear on pins and bushings of the undercarriage will vary with working conditions and type of soil, so inspect the
track tension every now and then in order to maintain the standard tension.
For carrying out inspection and adjustment of track shoes, park the machine on the flat and solid ground.
Checking
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. Put on the track shoe straight wooden bar (3) which
stretches from idler (1) to upper carrier roller (2).
3. Measure the maximum deflection between bottom surface
of the wooden bar and top surface of the track shoe.
Deflection "a" should be 10 - 30 mm.
If the track tension is not at the standard value, adjust it in the following manner.
Adjustment
There is danger of plug (1) flying out under the high inter-
nal pressure of the grease. Never loosen plug (1) more
than 1 turn.
Never loosen any part other than plug (1). Never put your
face in the mounting direction of plug (1).
If the track tension cannot be loosened with the procedure
given here, please contact your Komatsu distributor.
Increasing Track Tension
Prepare a grease pump.
1. Pump in grease through grease fitting (2) with a grease
pump. (Grease fitting (2) forms one part with plug (1).)
2. To check if the tension is correct, run the engine at low idle,
move the machine slowly forward (by an amount equal to
the length of track on ground), then stop the machine.
3. Check the track tension again, and if the tension is not cor-
rect, adjust it again.
WARNING
MAINTENANCE PROCEDURE
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