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Variable Speed Motor Removal


I often tell people there are 27 different ways to remove the motor, but only one right way. Before you leap into this, let’s look and think about a couple of things. 1. To get the motor out, you are going to have to find all the slack you can find in the variable speed drive belt. 2. When the instructions say, “disconnect the power” that doesn’t mean turn the switch off. It means exactly what it says, DISCONNECT THE POWER. Should you be holding the motor when your knee accidentally hits the switch, you are going to get hurt, really hurt and your $1,000.00 motor is going to be dropped and damaged. 3. The motor, together with the two pulley disks weighs about 60 pounds and you are going to be in an awkward position as you remove it so be prepared. OK, let’s begin. 

Step 1. It doesn’t matter if you have the mill head in HI range or LOW torque range. With the Speed Change Handwheel, run the head down to its slowest speed. This action will open the Variable Speed Pulley on the motor to its maximum. DISCONNECT THE POWER 

Step 2. Directly under the motor is the Motor Pulley Cover which is held in place with three, 10/32 x ¾” socket head cap screws. Take all three screws out and remove the cover.


What you’re looking at now is the spring collar. See those two holes? The hub on the Adjustable Motor Disk has two matching holes in it that are tapped. Insert two of the 10/32 socket head screws through these holes in the collar and screw them into the hub all the way. This will compress and secure the big spring on the Adjustable Motor Disk. 

Step 3. Go back to the front of the machine and turn the Speed Change Handwheel until the indicated speed is at its maximum. (The motor does not have to be running to do this.) This action opens the front variable speed pulley all the way. Now you have both pulleys wide open.


If you haven’t done it yet, DISCONNECT THE POWER 

Step 4. Electrically disconnect the motor. This can be done in three different ways. Our preferred way is to disconnect inside the Outlet Box which is mounted on the motor shell. You can also disconnect from the Drum Switch or you can disconnect the incoming power and remove the Drum Switch with the motor.


Step 5. Remove the two 9/16″ hex head bolts holding the motor to the Belt Housing. Move the motor forward slightly, tip the top of the motor to the rear and ease it up and past the variable speed drive belt. Sometimes the belt can be a bit stubborn and you will have to encourage it with a long screw driver but be careful. If you push to hard you can damage the belt. One last word of caution, the motor in your hands weigh about 60 pounds, BE CAREFUL! 

Below is a list of parts you may need during this operation: