National Crane 600H, Service Manual

Page: 149 / 232

NATIONAL CRANE
08-19-2022 Control # 092-13
6-11
600H SERVICE MANUAL SWING
6
8. Carefully lift the turret with bearing off the truck and set it
on blocking that will not allow the turret to tilt or shift.
Leave the lifting device attached.
NOTE: If the current bearing is to be reinstalled, mark the
position of the bearing on the turret before removal.
9. Remove all bolts from the inner race of the swing
bearing.
10. Lift the turret off the swing bearing and set on blocking.
NOTE: The bearing weighs about 415 lb (188.2 kg).
Check the bearing teeth for chipping or cracking. If any
evidence of these is found, replace the bearing. Ensure the
bolt holes are free of dirt, oil, or foreign material.
Installation
NOTE: If the current bearing is reinstalled, align the
marked teeth on the swing drive pinion shaft with
the marked teeth on the bearing.
1. Using an appropriate lifting device, set the turret on the
swing bearing. If the same bearing is being used,
position it as marked prior to removal.
2. Install new bolts and washers securing the bearing to the
turret. Refer to Inner Race Torquing pg 6-9.
3. Using an appropriate lifting device, align the turret over
the frame at the same position that it was before
removal.
4. Carefully lower the turret into position on the bearing
plate.
NOTE: If equipped, be careful not to damage the swivel
assembly.
5. Install all bolts and washers to secure the outer race of
the swing bearing to the T-box frame. Refer to Outer
Race Torquing pg 6-9.
NOTE: If a new bearing is installed, a new pinion gear
must also be used.
6. Install the swing drive pinion so that the high point
(maximum eccentricity) is aligned with the turret bearing
high point. Check the backlash with a (0.008 in)
0.203 mm thick shim ( pg 6-11Figure 6-13). If the pinion
must be moved to achieve proper backlash, contact your
local distributor.
NOTE: If equipped with a swivel, reconnect the hydraulic
lines as per removal tags.
7. Install the boom and lift cylinder following the procedures
outlined in Section 4- BOOM.
8. Reconnect the batteries.
9. Check the slew potentiometer for proper orientation as
described below.
DANGER
Do not reuse the swing bearing bolts. The swing bearing
is torqued to the applied torque of the grade 8 bolts. New
bolts ensure proper torque and bolt strength for securing
the swing bearing and turret to the frame.
!
0.008 Shim
Maximum
Eccentricity
Tooth
Pinion
FIGURE 6-13
REFERENCE ONLY