Morbark M20R - Mill Bearing Greasing Instructions

03/15 • 81
ROUTINE MAINTENANCE
The mill bearings support the mill shaft and should be cleaned and
repacked twice a year or every 1,000 hours.
1� Before performing maintenance on the mill bearings, follow
steps to shut-down the machine.
2� Remove the top of the bearing housing.
NOTE: Protect the bearing from exposure to dirt or moisture.
3� Inspect the bearing for contamination.
4� Remove as much of the old grease as possible from both
sides of the bearing and both top and bottom housings.
5� While rotating the shaft by hand, purge recommended grease
into the bearing through an exposed hole in the center of the
outside bearing race. Pump grease until clean new grease
exits between the rollers, taking care to remove the old that
comes out.
NOTE: This is done with the use of a grease gun needle.
6� Fill bottom bearing housing with EP2 rated grease so it is
level with the top.
After performing maintenance on the mill bearings, replace the top
of the bearing housing.
TO REPLACE THE BEARING:
1� Unbolt the bearing housing and lift off the top to obtain
access to the bearing assembly. Lift the assembly and shaft
from the bearing housing and remove old bearing.
2� Slide the inner grease slinger ring onto the shaft.
3� Slide the tapered sleeve onto the shaft. The threaded end
should be toward the outside.
4� Slide the bearing onto tapered sleeve. Match the inner taper
on the bearing.
5� Slide the washer onto the shaft. The tabs should be pointed
away from the bearing.
6� Install the nut and washer.
7� Tighten nut until it is snug against the bearing. Leave enough
space to install the expansion ring in step 9.
8� Install outer grease slinger. Repeat steps 2 - 8 for the
opposite side.
9� Place the bearing into the bearing housing ensuring that the
grease slingers on both sides mate with the grooves in the
bottom bearing housing. Check that they turn easily when full
weight of assembly is resting on the housings.
10� Install the expansion ring into the bearing housing between
the housing and bearing (on the drive side of the bearing).
Rotate and push down until the ring meets the bottom of the
bearing housing and the ends are equal on the side of the
shaft.
11� With the assembly weight on the bearings, use a feeler
gauge to take an initial reading of the internal clearance be-
tween the bearing rollers and the top of the bearing. Record
the reading.
12� With a spanner wrench, turn the nut in a clockwise rotation.
This will drive the bearing onto the tapered sleeve and de-
crease the internal clearance between the bearing rollers
and the top of the bearing. Continue turning the nut until the
internal clearance is reduced to the distance speci ed for the
shaft diameter in the OEM literature.
13� On the idler side of the assembly, pull the bearing to the
outside groove of the housing before tightening nut. That way
when tightening the bearing it will move towards the middle of
the housing.
14� Fill bottom of bearing housing with EP2 rated grease so it is
level with the top.
MILL BEARING GREASING INSTRUCTIONS