How do you open hoover s3639???????

You are better off taking it to a Service Centre. It has electronics board inside and would need to be tested. If it's the motor brushes, you could replace those, but if it is the motor itself, it is normally beyond economic repair. Many parts including the motor are discontinued by the maker.

https://www.google.com/search?q=s3639+vacuum+replace+motor

Here is the exploded parts schematics showing the screws to get in.

https://www.partswarehouse.com/Hoover-S3639-Windtunnel-Canister-Parts-s/1037.htm

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If you did all this already the motor is not having power, must be replaced.

If you would like a repair manual, we can special order one for you for your Hoover S3639. Call us at AAAA TEVA Monday through Saturday from 9am to 6pm MST. Our number here is 303-770-6321.

Under the front clear housing that holds the cleaning tools, you will see the words "Easy Open" at the top of the bag compartment cover. Pull down and towards you and the bag compartment should open up. It's held in with pressure.

www.repairclinic.com or www.hoover.com

Most common burning smell is the belt in the power nozzle. check & replace.

I’m happy to assist further over the phone at https://www.6ya.com/expert/robert_b96ba3f038cf317c

how old is it ?maybe the motor went south.take the cover off and see if you see any burn marks ,maybe you can narrow down the burnig smell.i don't charge people for helping i just enjoy helping.314-628-9153

I had the same problem with my Hoover s3639. The cord rewinder started squeaking, and retracted less and less of the cord each time, until it finally stopped retracting the cord at all. Here is what I did. I hope it will work for you as well. Open the covered tool storage and remove the tools. You should see three screws. Unscrew the screws. Remove the cover. You should see the motor for the vacuum and the cord rewinder. Between the vacuum motor and the white wheel where the cord is, you should see two brass wheels that turn into each other in order to operate the cord rewinder. Spray a small amount WD-40 between the two brass wheels. This should solve your problem.

R U SURE THAT IT IS NOT JUST A SAFETY CUT OUT SWITCH , SOME MODELS HAVE A BLACK BUTTON BEHIND THE BRUSH HEAD DIFFICULT TO SEE SOMETIMES

My Hoover S3639 on/off switch stopped working. I don't hear the 'click' any more. I removed the top of the vacuum but can't determine how to replace the switch.