determined by ear (the higher the motor speed the higher will be the pitch of
the sound). The two upper and lower cover screws (65) fasten to the fan
housing, which in turn contains the rear armature shaft bearing; hence if the
screws are adjusted too tight they will spring the rear bearing out of
alignment, and slow down the motor by preventing the parts from turning
freely.
REPAIRS
C. When Motor Does Not Run
.
C-1. Turn switch knob to No. 10 speed and check electrical outlet where motor cord.
is plugged in to see that outlet is in good order and that it supplies
electric current of the same voltage stamped on the bottom of the Mixmaster
base. Then check continuity of circuit through motor and cord with a test
lamp. Place tips of test wires on each prong of the wall plug fitted on the
end of the motor cord. Have the switch knob turned to No. 10 speed. If the
test lamp (50 watts) lights up to practically full brilliance it indicates
that the circuit is continuous through the motor and cord. Unless there is a
short through the motor housing, the motor should run. Test for grounds or
short circuits by putting tester wires on the bare metal part of motor housing
and on each prong of wall plug. A “ground” will be indicated if the lamp
lights. If a ground is not indicated, yet motor does not run, it is probable
that bearings are bound - see Section C-3.
C-2. If
ground is indicated by test lamp, remove terminal box cover screw (87) and
take off terminal box cover (84) where cord enters motor. Remove soft rubber
insulating cover (95) and examine wire connections for grounds or shorts. If
connections appear to be in good order, detach cord from motor by applying hot
soldering iron to connections and pulling the wires apart. Remove the cord.
Disconnect filter condenser ground wire from motor housing by loosening
condenser ground terminal screw (66). Remove terminal insulation box (96) and
motor filter condenser (69). Now check again for grounds between each of the
two projecting wires and the motor housing. If no grounds are present, a short
must have existed in either the cord or filter condenser that have been
removed from the motor. Check both. If, however, a ground still exists within
the motor, take motor apart according to Sections A-1 to A-8 and check for
grounds in each part which carries current by examining the part carefully and
testing with the tester lamp wires applied between each part and the motor
case. Do this before removing the part from the case. Check armature for
grounds by applying test lamp wires between a commutator segment and armature
shaft or armature laminations. Likewise, to test field coils for ground, apply
test wires between motor case and leads projecting from field winding.
C-3. If armature
or whipper spindle sleeves (l3 and 20) have seized in bearings,
take motor apart as described in Section A-1 to A-12. When spindle sleeve is
frozen the armature can be removed only by twisting in counter-clockwise
direction. Flooding with kerosene may be found helpful in removing tight
whipper spindle sleeves. After parts have been removed, clean bearings with
rag soaked in gasoline (or kerosene),
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