Marley Geareducer 20, Geareducer 20T, Geareducer 20.1 Instructions Manual

M A N U A L

Series 20, 20T & 20.1

STANDARD AND TYPE CC (EXTENDED FAN SHAFT)

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GEAREDUCER

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FIELD REPAIR–SERIES 20, 20T & 20.1 GEAREDUCERS

Field Repair
Instructions

JANUARY 1992 RM-20H

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Series 20, 20T & 20.1 Cross Section

Figure 1. Gear Match Numbers and Setting Data

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Field Repair Instructions

FOR SERIES 20, 20T & 20.1 MARLEY GEAREDUCER
STANDARD AND TYPE CC (EXTENDED FAN SHAFT)

GENERAL

Geareducers can be repaired in the field; however, major
repairs require the use of a fully equipped machine shop.
When field repair or replacement of parts is necessary, the
following procedure is recommended for the disassembly and
assembly of the unit. If any “O” ring, oil retainer or gasket is to
be re-used, care should be taken not to damage it during
disassembly. Parts which contain “O” rings or seals should not
be jerked or twisted past a shoulder or edge. These parts are
marked with an asterisk (*) in the description below. All “O”
rings, oil retainers, and gaskets should be carefully inspected
for damage before being reinstalled. Marley recommends that
new “O” rings and oil retainer be installed during a major
overhaul. Gasket is replaced by Permatex No. 2. See Figure
5, page 7.

DISASSEMBLY

Item numbers refer to Fig. 2, pages 4 and 5.

1. Remove drain plug (Item 1) and drain oil.

2. Remove outer ring of bolts (Item 2.1) in pinion cage cap
(Item 2.2) and remove pinion sub-assembly* (Item 2).

CAUTION: The thickness of this shim pack (Item 2.3) is
important in the resetting of the gears. The shim pack
should either be saved or carefully measured with a
micrometer. If the gears are to be replaced, record the
pinion setting distance that is etched on the pinion gear.

3. Remove bottom cap (Item 3).

4. Remove fan shaft disc (Item 5) and shim pack (Item 5.1)
and pull ring gear hub (Item 6).

CAUTION: The thickness of this shim pack (Item 5.1) is
important in the backlash setting of the gears. The shim
pack should either be saved or carefully measured with a
micrometer.

fan shaft disc and place bolts, or a hub puller can be used
by making a special plate; similar to the fan shaft disc, with
a clearance hole that will allow the puller to push against

The gear hub may be removed by using the

the fan shaft (Item 10). Loosely attach plate to gear hub
and pull against plate with hub puller. A metal disc should
be placed between the fan shaft and the hub puller to
protect the end of the fan shaft.

5. Remove water slinger* (Item 7).

6. Remove labyrinth ring (Item 8) and shim (Item 9).

7. Press or pull fan shaft (Item 10). The top bearing cup (Item

11) will be removed with the fan shaft.

8. Remove ring gear (Item 12) from ring gear hub.

PINION CAGE DISSASSEMBLY

1. Remove pinion cage cap* (Item 2.2) from pinion cage
(Item 2.4).

2. Remove “O” rings (Items 2.5 and 2.6).

3. Remove locknuts (Item 2.7) and lockwasher (Item 2.8);
then press pinion shaft (Item 2.9) out of pinion cage. This
will free tail bearing cone (Item 2.10). A hydraulic press or
jack is recommended for removing or assembling press fit
parts.

4. Press oil slinger (Item 2.11) and head bearing cone (Item

2.12) from the pinion shaft. Bearings must not be exposed
to dirt, dust or moisture.

5. Press bearing caps (Item 2.13 and 2.14) out of pinion
cage.

6. If oil retainer (Item 2.15) in pinion cage cap is worn or
damaged and is to be replaced, it can be removed with a
hammer and punch.

FAN SHAFT ASSEMBLY

1. Press or pull top bearing cone (Item 13) from end of fan
shaft.

2. Press or pull bottom bearing cone (Item 14) from fan shaft.

3. Press bottom fan shaft bearing cup (Item 15) out of case.

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