Manitowoc Grove RT770E Service Maintenance Manual page 237

RT770E
13. Attach a suitable lifting device to the four superstructure
lifting lugs (two at the boom pivot shaft bushings and two
at the lower lift cylinder pivot shaft bushings). Take in
cable or chain to remove slack. Do not pull up on the
superstructure.
WARNING
Ensure the superstructure is fully supported before
proceeding. Death or serious injury may result.
NOTE: It will be necessary to rotate the superstructure
while attached to the lifting device. Outer race bolts
can only be removed from the front or from under
the cab.
14. Remove the 40 bolts and washers securing the turntable
bearing outer race to the carrier.
WARNING
Ensure that any blocking material used is capable of fully
supporting the weight of the superstructure and will not
allow it to tilt or shift. Failure to do so may result in death or
serious injury.
15. Carefully lift the superstructure, using care not to
damage the swivel assembly, and set it on blocking that
will not allow the superstructure to tilt or shift, or rest on
the swivel. Leave the lifting device attached.
NOTE: If the same bearing is to be used again, mark the
position of the bearing on the superstructure so it
can be installed in the exact position before
removal.
NOTE: The bearing weighs between 585 kg (1290 lb) and
642 kg (1415 lb) depending on the bearing used.
Ensure the bearing lifting device is capable of
supporting the weight.
16. Place an adequate lifting device under the bearing and
remove the 44 bolts and washers securing the turntable
bearing to the superstructure.
17. Using the lifting device, remove the turntable bearing
from under the superstructure.
Inspection
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.
GROVE
Installation
Anytime a turntable bolt has been removed, it must be
replaced with a new grade 8 bolt. Death or serious injury
may result.
NOTE:
1. Using an appropriate lifting device, position the turntable
bearing under the superstructure. If the same bearing is
being used, position it as marked prior to removal.
2. Install 44 new bolts and washers securing the bearing to
the superstructure. Refer to Inner Race Torquing in this
Sub-Section.
3. Using
superstructure over the carrier in the travel position and
carefully lower the superstructure, being careful not to
damage the swivel assembly, into position on the carrier
bearing plate.
NOTE:
4. Install 40 new bolts and washers. Refer to Outer Race
Torquing, page 6-11.
NOTE:
Max
Eccen-
tricity
Point
Published 11/26/2014, Control # 447-05
WARNING
If the same bearing is to be used again, align the
marked teeth on the pinion shaft and the marked
teeth on the bearing.
Installation is in the travel position. Ensure the
swing lock is disengaged before attempting to mate
the bearing to the superstructure.
an appropriate lifting
It will be necessary to rotate the superstructure
while attached to the lifting device. Outer race bolts
can only be installed from the front or from under
the cab.
If a new bearing is being installed, a new pinion
gear must also be used. Align the high point
(maximum eccentricity) on the bearing with the
new pinion gear high point.
Pinion
SWING SYSTEM
device, align the
6
.008 Thick
Shim By Full
Width To
Tooth
Engagement
(.016
Backlash)
FIGURE 6-4
6-13