SECTION 5 – SWING DRIVE
3120933 Rev. 0
USTC
5-9
evaluated by the bearing manufacturer to determine
on a case by case basis if the bearing requires
replacement.
Note: Ensure bearing bolts are properly torqued
before taking measurement.
1. Place the crane in an operating position with the
outriggers set.
2. With the boom horizontal and fully extended,
use a dial indicator to measure and record the
distance between the outer race of the swing
bearing and pedestal. Measure at the opposite
side of the boom.
3. With the boom at horizontal and fully retracted,
place a suitable (5 ton) hydraulic jack between
the deck and the boom. Raise the boom enough
to reverse the load on the swing bearing.
4. At the rear center of the pedestal, measure and
record the distance between the swing bearing
and pedestal. If the distance is greater than
0.072 in. (1.829 mm), then it may be necessary
to replace the bearing. Contact the Service
Department for additional instructions regarding
the evaluation process.
Outer
Measure Here
Teeth
Turntable
Inner
Pedestal
Figure 5-6. Swing Bearing Clearance Measurement
Figure 5-7. Bearing Tolerance Check
