Coin Slot Magazine - #077 - 1981 - July [International Arcade Museum]
( PUT ANOTHER NICKEL IN
J
Art Reblitz
SERVICING OLD ELECTRIC MOTORS
The motive power for many old amusement ma
or othertiny marks in places where they won't be seen
chines, including coin pianos, orchestrions and juke
after reassembly, so you will know exactly how to put
boxes, is an electric motor, usually an alternating
everything back together later. Take nothing for gran
current induction motor. Most motors made during the
ted! In every instance of disassembling parts, mark
era from 1900-1945 used in coin operated machines
were made to last many lifetimes with proper care.
something won't go back together right because of
them or make a sketch. It will be perplexing later when
Some of these motors had good care over the years, and
some didn't, but many still have years of useful life
poor marking or sketching.
provided that they are properly cleaned and lubricated.
again
The focus of this article is on maintenance, not repairs.
Maintenance can be done with a few tools, but repairs
bearing. Clean the end bells and mounting base in
solvent — mineral
should be made by a competent electric motor repair
noting first whether the solvent will turn the surface of
shop.
the black enamel whitish or leave any other residue.
The life of a motor is dependent upon how clean it is
Remove the other end bell from the motor body,
noting any washers which are stuck to the
spirits or some
other cleaner —
Carefully clean all of the old lubricant from the oil or
kept, how carefully it is lubricated, and the care and
grease cups with pipe cleaners, Q-tips, and clean lint-
feeding of the starting switch. Most induction motors
free cotton rags. Replace string packing or wicks if
have two windings: a powerful starting winding which
necessary. If the paint is bad, mask off the bearing and
comes on every time the motor is turned on, starts it
rotating in the right direction, brings it up to speed and
surface and paint with
then shuts off; and the running winding, which keeps
high gloss black enamel.
mounting surfaces for the starting switch, prepare the
high temperature-resistant,
the motor going once the high torque of starting is no
With an artist brush and air hose, remove as much
longer necessary. The starting switch has contact
loose dirt as possible from the windings in the motor
points which turn thecircuit on to the starting winding
body. Do not dip this or any other parts having wires
when the motor is at rest, and turn it off by centrifugal
attached in solvent, as the solvent might cause the
force once the motor is up to a certain speed.
To properly clean a motor, the case must be taken
insulation to deteriorate later, particularly if it is mar
ginal to begin with. If any insulation is flaking or coming
apart. Remove the mounting base, if present. Discon
loose from the windings, leaving exposed wire, have
nect any wires attached to binding posts, sketching
their correct hookup. Remove the nuts or machine
the motor rewound by a good motor shop. If the motor
screws around the perimeter of the end bell which
contains the starting switch and wires. Some motors
have three or four tiny rectangular notices around the
motors) the shop will replace it at the same time.
seam between the end bells and the main body, for
every time the motor comes up to speed. Starting
insertion of a screwdriver blade; others have no notches
switches were made in all imaginable shapes and
has a commutator (a rare feature in AC induction
Examine the starting switch. This is the part which
most often causes problems because it sparks a little
and require the use of a chisel. Whichever tool is used,
mechanical configurations. Use your ingenuity to re
pry just a tiny amount at each point and then go to
store the electrical contact surfaces of the switch. If it
another to keep from distorting the bearing, housing or
is beyond repair, an undamaged old switch will have to
shaft. When the end bell is popped off the body, slip it
be found at an old motor repair shop, or the parts will
(and the armature if necessary) out of the rest of the
have to be fabricated by a machine shop. I n most cases
motor and lay them on a towel on the bench to keep
when an old motor refuses to start when plugged in,
parts from rolling off. The bearing in the end bell and
the starting switch — not a bad winding — is the culprit.
the armature usually have fibre washers hanging on by
When the switch is clean, shiny and smooth as new,
old grease; make note of where the washers go for
reinstall it to its end bell.
om
m.c
reassembly later. The armature will usually come off
m: useu
o
r
f
centrifugal switch. Wires
bell to
ed connecting
de-m the if end
a
oad . be
the main body
should
disconnected
possible. If
l
c
r
n
ow to w terminals
w a
they are D
attached
or binding posts on the
w
/
/
:
end bell, remove
the
wires;
if
they
are soldered to the
p
htt
the end bell by manipulating the moveable parts of the
starting switch stator (the stationary part of the switch),
At
this
point,
check the
insulation
on
all wires
associated with the starting switch and binding posts.
In many cases, the insulation on these wires is bad,
even when the motorwindings are still good. If there is
room to replace the old leads with
new ones by
soldering close to the windings, do so; or if there is no
room,
it is sometimes possible to add a piece of
remove the whole switch from the end bell without
unsoldering the wires. Make small identifying scratches
© July
The 1981
International Arcade Museum
Continued on page 38
http://www.arcade-museum.com/
THE COIN SLOT—37