OK, you've suffered long enough. Time for me to fess up. Empires are old designs (very good, lasting the test of time), but, they engineered somethings that I always questioned. First, their huge high-torque motors are almost industructable. You could use them in a record cleaning machine as the drive motor.
We all know that synchronous motors lock onto line frequency to hold their speed. That almost never veries, but voltage does, thats why they are designed this way. Another way to determine a motors RPM is 120 X cycles (60)/ number of poles. Most modern day motors are 24 pole (that puts the half cycle pole position every 15 degrees) so the equation works like 120 x60 = 7200 /24 = 300.
The Pabst motor in all of the Empires, runs much faster. When I did the math years ago, things didn't quite come out, cause I also don't know how many poles there are, but it's way more then 24. I also know this is an inside out rotor motor. Not ever taking one apart, this portion is a mystery to me, but along with the math, I could tell the motor was designed to run faster then the spec speed of 33 1/3 RPM.
Why did Empire do this? Well, If the tables were to survive years and years of service, you could imagine that they would get dirty and start to slow down. Because it's a synchronous motor, you can't make it speed up, the only way to adjust was to slow it down. So my guess is they designed it at a faster speed on purpose.
If you look at your motor assembly, you will notice a knurled nut. As you loosen or tighten the nut, you will notice that the motor starts to tip towards or away from the platter. If you tip it far enough (away), the edge of the belt will hit the edge of the next pulley. This is how Empire adjusted the speed of the motor, by putting more drag on the motor (physically). You did not ever move the knurled nut far enough to ever observe that (It took me awhile to figure this out, too.
Now here is the fix: I wrapped the path of the drive belt around the rim of the drive platter with electrical tape, keeping out all the bubbles, keepint the tape always straight and stretched (almost none) the same as I went around and around. The end of the tape should be at the original seem and cut straight so that layers do not overlap. It will end up about 1/8" thick all around. Your speed will be perfect.
Wayner
