Hi All,  A common problem with the Wurlitzer 1203 vacuum motor
involves an accumulation of carbon dust in the brush holders.  Over
the years, the dust blows into the holder and the brushes get stuck.
After a fairly short while, the brush no longer makes contact with
the commutator and the motor quits working.

Opening the motor housing (a thick cardboard cylinder) can be kind
of tricky because it's stapled together, but once the motor is
removed, removing the brushes assemblies is very simple.  After they
are removed, place the brushes in a jar with acetone and shake it
a little (don't get too aggressive).  The dust will wash out and the
brushes will once again move smoothly in and out.  Put everything
back together in reverse order, and you're set for another 20 years.

By the way, you can test the motor with 120 VAC if you wish.  But,
I always check to see if the motor is getting the operating voltage
before I take it apart.  I've never encountered a situation where
there was no voltage to the motor.  In every case, the brushes were
the problem.

Musically,
John A Tuttle
Player-Care.com
Brick, New Jersey, USA