I have a Lenco L75 that I'm rebuilding for the stoep.
The motor had a tick, sounded like something touching a piece of tape, like the sound of an old movie projector but a wee bit slower. I serviced it twice, once lubricating it with machine oil and the second time with heavier grease. No change to the ticking. What puzzled me was that it did not tick when I spun it by hand. I could not influence the tick, except frequency, by touching the running spindle. The little pressure grub screw at the nose of the motor also had no effect, except binding the motor when too tight.
I remembered from watching some guitar pickup making videos; guitar pickups are wax potted to make sure loose windings doesn't vibrate in sympathy with the magnetic fields and cause distortion. So, I hypothesized that this might be the problem. Ticking like that the motor was done for anyway; time to try something wild.
I melted some candles, removed the stator from the motor, dunked it in the molten wax, and left it there until the bubbles stopped rising from the windings, and the wax started to get cloudy. I removed it, cleaned it up a bit, and reassembled it; lo and behold, no more ticking.
and ...
The motor had a tick, sounded like something touching a piece of tape, like the sound of an old movie projector but a wee bit slower. I serviced it twice, once lubricating it with machine oil and the second time with heavier grease. No change to the ticking. What puzzled me was that it did not tick when I spun it by hand. I could not influence the tick, except frequency, by touching the running spindle. The little pressure grub screw at the nose of the motor also had no effect, except binding the motor when too tight.
I remembered from watching some guitar pickup making videos; guitar pickups are wax potted to make sure loose windings doesn't vibrate in sympathy with the magnetic fields and cause distortion. So, I hypothesized that this might be the problem. Ticking like that the motor was done for anyway; time to try something wild.
I melted some candles, removed the stator from the motor, dunked it in the molten wax, and left it there until the bubbles stopped rising from the windings, and the wax started to get cloudy. I removed it, cleaned it up a bit, and reassembled it; lo and behold, no more ticking.
and ...