A good simple switch. I bought several so I would have a common system on all machines. Haven't gotten around to replacing all of them yet though. It's "in the works"~~~ They're Chinese, but are rated at several times the load of a fractional horsepower motor. We shall see~~~
To answer your question:
There are two seperate but related portions. The first is as a line switch. Take the two wires from/to the power switch and locate them on the top contact. That's the easy one. I would suggest the line side, or power cord be to the left. Not an absolute, just the way I think.
The second portion is to find the two wires that are for the start winding of the motor. This is where your buddy may come in handy. Remove them from the "lugs" or "stabs" on the motor. Route them to the left side of the switch, the middle and bottom. From the right side, again middle and bottom, route two wires back to the motor, connecting them to the points from which you removed the wires earlier.
Make sure the green wires have not been disrupted. They are a safety ground and should never be disconnected on a functional machine. I, and any other decent electrician, will be obsessed with this wire. The wire need not be connected in the switch, it's all plastic, an insulator.
The motor is ready for a test run. Hook it up and try it. If the motor runs backwards, swap the leads on the middle and bottom right. Forward and backward are relative. I run my machines backward from the labels because of my positioning of the switches. Again, just the way I do things. Make it comfortable for you, instinctive motions.
There are several possibilities to make the connections, depending on how things are routed. The line cord can come into the switch first, which would require the neutral or white wire be passed on to the motor with no connection in the switch.
Most of my machines, and my preferred method, is to bring in the line cord to the motor and use a single 7 conductor rubber cable to the switch. It does take a lot of space at the motor, though.
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