TM 9-4110-258-13
4.31 V-BELT REPLACEMENT AND ADJUSTMENT.
This task covers:
a. INSERT FUNCTION
b. INSERT FUNCTION
c. INSERT FUNCTION
INITIAL SETUP
Equipment Conditions:
General Safety Instructions:
Refrigeration unit shut down (para 2.7) and power
WARNING
disconnected.
Left side door open.
Left side door open.
High voltage and exposed rotating parts are
Front door open.
used in the refrigeration unit. Personal injury
can result if power is connected.
a. Removal.
(1) Turn self locking nut (1) counterclockwise enough to allow motor mounting plate (2) to be lifted enough to slip V-
belt (3) off pulley (4).
(2) Remove four bolts (5) and flat washers (6).
CAUTION
Moving the fan drive shaft too far can cause damage to the evaporator fan or coil.
(3) Loosen two set screws (7) and carefully move fan drive shaft (8) just enough to work V-belt (3) around front
bearing channel (9) and condenser fan (10).
b. Installation.
(1) Work V-belt (3) around front bearing channel (9) and condenser fan (10).
(2) Move fan drive shaft (8) to align front bearing channel (9) mounting holes and install four flat washers (6) and
bolts (5). Tighten two set screws (7) against flat surfaces on shaft.
(3) Slip V-belt (3) over sheave (11) and pulley (4).
(4) Adjust belt tension.
c. Adjustment.
(1) Check alignment of pulley (4) and sheave (11). If they are not alignd, loosen set screw (12) and move pulley on
AC motor (13) shaft as necessary. When alignd, tighten set screw.
(2) Turn self locking nut (14) clockwise several turns to allow free travel of motor mount plate (2).
(3) Turn self locking nut (1) clockwise to increase V-belt (3) tension and counterclockwise to decrease tension. V-
belt tension is correct when 4 lb (2 kg) force is applied to the mid point of the V-belt and it deflects 3/8 in. (1 cm).
Turn self locking nut (14) clockwise as necessary to allow motor mount plate (2) travel.
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