Hoover Wiring differs by models
If I could ask, what are you trying to build, Kirbykid?
The Hoover canisters of the Windtunnel, PowerMax and Futura style have the receptacle from electric current to the hose located in the bottom left inside the front carry handle. The wiring travels along the bottom of the unit covered by a black plastic piece about 1" wide going the length of the canister. From there they enter the suction unit tank at the very rear behind a plate and split off. One connects with a lead wire from the carbon brushes to the cord reel. The other from cord reel to on/off switch I believe.--Would have to open up one of my vacs to be certain!! Some models had a separate on/off switch for the power nozzle agitator and had 3 wires coming from the power head. All of that function as would be on the Windtunnel Plus S3639 was controlled by a circuit board and switch in the hose handle. From the switch, the wiring was reverted back to 2 wire circuitry where it connected to the receptacle at the suction unit. Very similar to the S3639 would be the Gray Hoover Preferred Windtunnel Canister S3641, a Lowe's Exclusive. Had the same tool lid with turbine hand tool as the blue S3639. Also Hoover Turbo Power 7000 S3646 or S3646-090--had the turbine powered hand tool. A TurboPower 7000 is pictured below S3646.
The Windtunnel Ultra lines S3655, black, or S3661 translucent green, Turbo Power Windtunnel 7500 model S3649, PowerMax Ultra S3620 dark green, or PowerMax Supreme S3611, dark green and many of the Spectrum models had more complex wiring. Those models had controls on the handle for not only on/off of agitator motor but also on/off switch for entire power to the vacuum as a whole and also sliding electronic variable speed control. Those units stayed 3 wires entering back into the suction unit and as I've never owned one of those machines, I wouldn't be able to say how else they were wired and where they connected once inside the suction unit. I know many units of that style had a small red light that would be lit just infront of the upholstery nozzle under the tool lid. That light meant, that the power switch on the suction unit was on if red, and the user would then be able to control power for the vacuum at the hose handle. If the power switch was turned on at the suction unit, then the hose handle switches had no power.
You may want to search on eBay, I remember a Buy It Now for Hoover Windtunnel S3639s, there may still be a listing for one in july or so. It would be far back. Search "Hoover" Canister, or you may try "Hoover" Windtunnel. eBay made changes to their browser. If you don't put in quotation marks for "HOOVER", then you 10,000 other miscellaneous listings that have nothing to do with Hoover, they just come up. I have no idea what eBay did. I've heard someone spoke to them on the phone about it and they played dumb!!
You may be able to talk with Guardsman69, John Gregory on this site and he may be able to help you out some as well. He operates the longest running Hoover Factory Authorized Service Center.
