Check Track Sag (Rubber Crawler) - Hitachi EX27U Operator's Manual

Check Track Sag (rubber crawler)

--- every 8 working hours
Proper track sag adjustment is necessary to extend the
service life of the rubber track and the travel device.
Check Track Sag
1. Position the blade to the rear of the upperstructure.
Lower the bucket and blade to raise both tracks off
ground, as shown. Place blocks under machine
frame to support the machine.
2. Rotate the rubber track so that the track joint is posi-
tioned at the upper center of the track.
At the center lower roller, measure distance (A) from the
bottom of the lower roller to the inner ridge of the rubber
track.
Track Sag Specifications (dimension A): 10 to 15 mm
(0.39 to 0.59 in)
Precautions for Adjusting Track Sag
1. If track sag is not within specifications, loosen or
tighten the track following the procedures shown on
the next page.
2. Before adjusting track sag, lower the bucket and
blade to the ground to raise both tracks off the
ground as shown above. Be sure to place blocks
under machine frame to support the machine.
3. After adjusting track sag of both tracks, run the
tracks back and forth several times.
4. After doing so, check track sag again. If track sag is
not within specifications, repeat adjustment until cor-
rect sag is obtained.
MAINTENANCE
7-58
A
Joint
Joint
Lower Roller
A
Rubber Track
M586-07-004
M552-07-096
M102-07-075
M503-05-050