XCLIO WINDTUNNEL MANUAL

http://www.vacshopusa.com/windtunnel.htm
it is cost $4.99

click this link below to see repair video for self propelled mechanism
http://www.youtube.com/watch?v=K722IsUxjYM&feature=related

The problem is that the belts are stretched and worn and slip instead of turn the brush when it is put against the resistance of the carpet. You simply need to replace the belts. Here are the (2) belts you need and the manual with instructions:

Hoover self-propelled windtunnel belts

Manual

You need to replace the belts. Here are the (2) belts you need and the manual with instructions:

Hoover self-propelled windtunnel belts

Manual

You probably need to change the belts. Here are the belts you need and the manual:

Hoover 5780-900 Belts

Manual

Here is a link to the manual and to the belts you need.

U6439-900 Manual

U6439-900 Belts

Below I have listed a link to the manual which has instructions and a link to the V belt you need.

Windtunnel Manual

Windtunnel Replacement Belts

You need to replace it periodically. Below I have listed a link to the belt you need and a link to the manual which has instructions.

Hoover U6634900 Replacement Belts

U6634900 Manual

Try calling Hoover directly toll free at
1-800-944-9200 M-F 8 AM - 7 PM EST.

OK - sounds like your machine has a blockage somewhere. Follow manufacturer's instructions for clearing blockages and all should be well. If you no longer have the manual, you can download it from the Hoover website.
Good luck!