Upper Slow Motor

[Jaim]

The upper slow motor in my 21H (converted to 2 speed operation) isn't engaging the disk. I readjusted it so it doesn't touch the disk and noticed that the armature only comes even with the top of the shading coil. Others I have seen, the armature centers itself on shading coil. Bearings are oiled and the motor spins freely. I could remove the washers which position the slow motor in relation to the fast, but it appears the motor is a little weak.

So - is the motor going bad?

Other than the spring and spacer location; is there any difference between the upper and lower motors?

Jim

[Sweet Pete]

Page 10 in my 122 Service Manual has an 'exploded' view of the upper and lower slow motors.
I would double check my work against the diagrams.
Unlikely a small/slow motor will be 'weak'.
In my experience they work or they don't.

The 'thru' bolts are opposite ends on upper
and attach from above, bolts enter from below.
Hope this helps.

[jdoc]

depending on the position vertical/horizontal/up/down there is a helper spring. Not knowing what motor you salvaged and you have installed I would start there, spring is critical in some positions and must be installed correctly.

[Jaim]

Thanks for the responses. If I remember correctly, I put this stack together about 8 years ago. The fast motor is a little stiff so I'll disassemble, clean, oil, reassemble and adjust the upper stack. I'll also check the o-ring for flat spots.

Thanks again,

Jim

[jdoc]

what was it originally out of, orientation is everything due to the spring setup, i have converted a few to differnet positions than designed, ToneWheel General sells the springs iirc

[Jaim]

Rebuilt the upper stack - all is well. The metal washers in both motors were pretty worn. During a rainy day shop cleanup, I found a set of Leslie motor refurb kits I had ordered years ago - came in handy.

I really don't understand why the slow motor wouldn't raise the last 1/8". I could push it up, but it wouldn't stay. Maybe the bearings were gummy enough to drag it down.

Thanks again for the advice,
Jim

[jdoc]

good to hear

[johnny b3]

Often times the drive spindle will wear away the upper bushing in the direction opposite the drive tire (probably because of being adjusted too tightly over the years). The bearing will develop a notch which will interfere and cause strange problems such as what you describe, even if recently cleaned and oiled. The springs have nothing to do with helping the armature's energized position. See if you can find any lateral play in the slow motor's upper bushing.

[jdoc]

unless the spring is on the wrong side........never say never, but JB3 is right.

[Goff]

if i understood the problem, it's usually the spring is worn out. get the right fresh spring in there and the motor should work fine. the bottom slow motor's spring is a different gauge wire than the top slow motor's spring. and these springs do wear out especially on the upper motor stack because the spring is having to lift the armature after being compressed most of the time. that is a lot of work going on for that little spring.

it helps to have spare new springs for both top and bottom rotor. these springs go bad all of a sudden.

it's a delicate adjustment to get the spindle to set next to the rubber tire without being too tight or too loose. a fresh spring also gets rid of the "knock" you hear when the leslie is switched from slow to fast and the armature drops down in the case of the upper motor stack. this is the sign the spring is getting weak as it's lost its strength.