Hitachi ZAXIS 17U-2, Operator'S Manual

Page: 158 / 183

MAINTENANCE
7-55
Check Track Sag (steel crawler)
--- every 50 working hours
Proper adjustment of track sag is vital to extending the
service life of the track and travel device.
Check Track Sag
As illustrated to the right, raise the one side track, which
sag is measured, off the ground. Place blocks under
machine frame to support the machine.
Track Sag
Specifications
Dimension
85 to100
A in mm (in.)
(3.3 to 3.9)
NOTE:
•
Check track sag after thoroughly removing
soil stuck on track area by pressure washing.
•
When operating the machine on ground such
as mud or gravel, these materials may easily
become packed into the undercarriage,
adjust the track sag so that it is slightly loose.
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. When adjusting track sag, lower the bucket to the
ground to raise one track off the ground. Repeat this
procedure to raise the other track. Every time, be sure
to place blocks under machine frame to support the
machine.
3. After adjusting track sag of both tracks, move the
machine back and forth several times to equalize the
track sag on both side tracks.
4. After doing so, check track sag again. If track sag is
not within specifications, repeat adjustment until the
correct sag is obtained.
M1M7-04-006
M588-07-062
A
90 to 110
°