I received a message from Randy Blake asking about the "non-fluid" oil
recommended in the little "Instruction Book for Holtzer-Cabot Special
Noiseless Piano Motors."

Certain Duo-Art upright motors have the problem of oil running out of
the bearings into the inside of the motor case and onto the windings.
This is an important issue.

I recently did my usual test on an unrestored Holtzer-Cabot Wurlitzer
motor by plugging it in for a brief moment, just to see if it would
start turning.  This motor has relatively big oil reservoirs and splash
rings (earlier and less refined than the type of motor used in
reproducing pianos).

The oil-soaked insulation instantly started burning like the wick of
a kerosene lamp.

Here are my recommendations:

I have never found the "non-fluid" oil recommended in the old booklet.
When we clean an old motor, I remove the old wicking, clean it in
lacquer thinner, stuff it back in and saturate it with SAE 30 weight
non-detergent motor oil.

In some motors, the wicking is really packed in tightly and can be
a challenge to get out without damage.  I've found replacement wicking
at an electric motor repair shop, but I'm not sure if it's still made
today.

If a little oil slowly oozes out of the motor where you can wipe it
off, that's okay.  Whenever I remove the belly cloth of a grand piano
I check for oil on it, under the location of the motor, before laying
it on something and possibly making a mess.  In an upright, I just look
at the motor periodically and wipe any oil off the outside.

To prevent the oil from running inside the motor, I try not to put too
much in -- just enough that the wicking will hold it and release it as
necessary.

In an upright, keep an eye on the motor and keep wiping any excess oil
off as soon as you see it.  If this is unsatisfactory, see what a motor
shop recommends.

Above all, never pack the oil reservoirs in a motor with any kind of
grease.  It will not provide proper lubrication and will cause the
motor to slow down, stall and overheat.  I've seen this happen when a
public attraction owner packed grease in the oil reservoirs of a Mills
Violano AC/DC rotary converter.

Input to the MMDigest on others' experiences with this problem will
be welcome.  Exactly what was "non-fluid" oil?

Art Reblitz