Model 50 service manual, SM50LD2-AB Page 3
Eskridge, Inc. Olathe, Ks. 913-782-1238 www.eskridgeinc.com
Unit Teardown
1) Scribe a diagonal line across the outside of the unit from the
cover (3) to the base (1) before disassembly to aid in the proper
positioning of pieces during reassembly.
2) Remove drain plugs (30A) and drain oil from unit. The oil will
drain out more quickly and completely if warm.
3) Remove the 12 7/16-20 capscrews (25A) and lockwashers
(25B) securing the cover.
4) Remove the cover (3), thrust washer (14B), and input gear (4).
Inspect o-ring (16B); discard if damaged or deformed.
5) Lift the planet carrier assembly out of the unit .
6) Remove ring gear(s) (12) and subsequent carrier assemblies
and thrustwasher (14A). Inspect gear to gear and gear to base
O-ring(s) (16B); as before, discard if damaged or deformed.
7) The unit is now disassembled into groups of parts. the area(s)
requiring repair should be identified by thorough inspection of
the individual components after they have been cleaned and
dried.
Carrier Assembly Teardown
Rotate planet gears (7B pri/5B sec) to check for abnormal
noise or roughness in bearings (7D pri/5D sec). If further in-
spection or replacement is required, proceed as follows.
1) Drive roll pins (7F pri/5F sec) completely into the planet shafts
(7C pri/5C sec).
2) Slide planet shafts (7C pri/5C sec) out of carrier (7A pri/5A
sec).
3) Remove planet gears (7B pri/5B sec), washers (7E pri/5E
sec) and bearings (7D pri/5D sec) from carrier (7A/5A).
4) Inspect the planet gear (7B pri/5B sec), bearing bore and plan-
et shaft (7C pri/5C sec) and bearings (7D pri/5D sec). Check
for spalling, bruising or other damage and replace components
as necessary.
5) Remove roll pins (7F pri/5F sec) from planet shafts (7C pri/5C
sec) using a 1/8” (pri) or 3/16” (sec) pin punch.
Carrier Reassembly
1) Planet shafts (7C pri/5C sec) should be installed with cham-
fered end of 1/8”(pri), or 3/16”(sec) roll pin hole towards outside
diameter of carrier (7A pri/5A sec); this will ease alignment of
holes while inserting roll pins (7F pri/5F sec).
2) Drive roll pin (7F pri/5F sec) into the carrier hole and into plan-
et shaft to retain parts. Repeat for remaining planet gears.
Base Subassembly Teardown
1) Remove the shaft retainer lock ring (35C) using a heel bar or
puller; if using a heel bar, be sure not to pry against the cage
of the inner output shaft bearing (20C). Remove the split ring
segments (35B) and shims (35A).
Caution: Since the shaft is no longer positively retained,
care should be taken to avoid personal injury. Care should
also be taken not to damage it while pressing through
base.
Note: Removing the shaft from the base assembly damages
the shaft seal. The seal will need to be replaced.
2) Place base (1) external side down, supported at the case
perimeter. Press output shaft out bottom of base by apply-
ing a load to internal end of shaft until it passes through
inner shaft bearing cone (20C).
3) A gear puller may be used to remove the outer bearing
cone (20A) from the shaft (2). If reusing old bearing cone,
donotpullonordamagerollercage.If shaft bearings show
evidence of wear or damage they should be replaced at
this time. Remove the shaft seal (16A) for inspection or
replacement.
Note: When installing new shaft bearings. press the bearing
cone onto output shaft by pressing on inner race only. DO
NOT press on roller cage, as it will damage the bearing.
4) Lubricate inner lip of new shaft seal (16A) and slide it onto
the shaft (2) until it fits snugly over the shaft seal diameter
with the open side toward the interior of the gear drive.
5) Inspect inner and outer bearing cups (20D & 20B). If cups
are damaged, drive them out using a brass drift and utiliz-
ing the bearing knock-out notches in the base (1)
Base Reassembly
1) Clean all foreign material from any magnetic oil plugs lo-
cated on base (1).
2) Place base exterior side up on work table.
3) Apply a layer of lithium or general purpose bearing grease
to the roller contact surface of outer bearing cup (20B).
4) Press outer bearing cone (20A) onto the shaft until it seats
against the shoulder.
5) Place the shaft (2) with the bearing cone (20A) into the
base.
6) Flip shaft/base assembly, and apply lithium or general pur-
pose bearing grease to roller contact surface of the inner
cup (20D), then press inner bearing cone (20C) onto shaft
until it seats against inner bearing cup (20D).
7) Prior to installation of the shaft seal (16A), the pre-
load may result in a rolling torque which varies be-
tween 50 to 80 in-lb. The bearing preload should be
tailored to your application; a low-speed application may
require a high pre-load, while high-speed applications
usually benefit from low pre-load. Adding shims (35A) will
increase the pre-load on the bearing set. Determine your
pre-load requirement and install shims to obtain this pre-
load.
8) Install the Load-N-Lock™ segments (35B) over the shims
