How to tighten pulley on Hoover U6630-900

Turn the machine over and remove the 4 screws which hold the cover on the brush. Remove the cover and brush roller. Remove old belt. Slide new belt over the motor pulley, first. Then slide roller through new belt (if self propelled model, slide roller through the small belt, also) and slide brush roller into slots on housing (note: slots are different, match roller sides to correct slot.)

There are two belts on this machine. The belt on the brush roller will appear loose when in upright locked position. Releasing the handle to an in use position releases a spring loaded idler pulley which increases tension on the brush roll driving belt. Check whether pwr on/off button flashes when attempting to turn on. This may indicate an obstruction or faulty sensor.

I also have a loose belt and have bought additional belts but have the same problem. I put the it around the metal rotor and around the brush roller a shown by he Hoover video, and it is loose.

thats why the brushes wont turn,, the belt is slipping put a new belt on then try again,,,

take it in for diagnosis - seems to be an offset perpenducular drive axis.. seems to me.

when you released the end to slide the new belt on it allows the tension roller to slide into the wrong position. Remove the top so that you can see the roller, at the left side of the roller mechanism there is a screw, loosen it enough to allow the roller to return to the correct position.
good luck

here are the step by step instructions from the owners manual for your machine.
Disconnect cleaner from electrical outlet. WARNING: Agitator brush roll can start suddenly. Unplug cleaner before turning it over. Replacing Flat Belt Place handle in low position and turn cleaner over so bottom side is facing up. Remove the 6 screws as shown with a Phillips screwdriver. Lift off bottom plate. Replace belt if it is stretched, cut or broken. To check the flat belt. Removing Bottom Plate Removing Belt Positioning Belt Remove used belt from large pulley and discard. Reposition bottom plate and 6 Phillips head screws. Tighten screws securely. Insert agitator brush roll through belt and position belt in groove (A) on agitator brush roll. Inspecting V-Belt The V-belt is designed to last for a long time and is not normally replaced. However, if the V-belt is cracked, gouged or broken, it should be replaced. Slide flat belt off large pulley. To remove V-belt, slide back of belt over pulley (A). Then firmly pull on belt and “snap” it out. Discard used belt. To install new belt (with lettering on outside of belt), slide back of belt over pulley and pull front of belt toward groove next to pulley. Belt will “pop” into place. Flat Belt: What to Buy Use only genuine HOOVER belts with your cleaner. When purchasing a new belt, ask for Flat belt - HOOVER part No. 40201-271. V-Belt: What to Buy Use only genuine HOOVER belts with your cleaner. When purchasing a new belt, ask for V belt - HOOVER part No. 40201-200.
If you can't get the answer from this post, send me a message and I will try to walk you through this. I hope it helps.

change the other belt as well even if it isnt broken, the v belt will look loose but it isnt there is a tension pulley that comes down on it when the handle is released. if that doenst do it the tension pulley itself could be broken. also check the rug floor knob if its over even a little bit it could stop the brush from turning.

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Generic problem for all Vacuums
New main belt alignment for
Posted by donlee300 on July 29, 2008
New main belt alignment for Hoover Windtunnel Mach 6.1.
Belt moves 1/4 inch towards of vacuum cleaner and will not stay aligned on the V convex guide pulley.
Hello,
I would advise you to ALWAYS to FIRST UNPLUG YOUR VACUUM before beginning any service procedure. It is possible that you may have a broken or cracked motor mount and the motor has shifted and that could be the reason that the belt is not running straight and aligned properly – if you have the vacuum less than one year – something like this would be covered under the Hoover factory warranty and to contact an authorized Hoover vacuum cleaner dealer in your area or to call the Hoover factory cust serv @ the phone # listed below. So if you need further assistance, please feel free to contact your local vacuum cleaner dealer in your area or in the yellow pages, or contact the factory phone number or website to further assist you with your questions.
http://www.hoover.com Telephone
Contact our Customer Service Department at 1.330.499.9499
Monday through Friday
8 a.m. - 7 p.m. EST
Thanks, Don the Vac Man
Go Ahead. Use Us.

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Generic problem for all Vacuums
I have a Hoover Vacuum
Posted by Jimbob48 on Jul 01, 2008
I have a Hoover Vacuum Cleaner, Runabout Supreme, on which the belt has broken. I purchased a new belt, part number 38528-040.
I need some instructions on how to install the replacement belt? Thank you. JBS

Hello,
I would advise you to ALWAYS to FIRST UNPLUG YOUR VACUUM before beginning any service procedure. Usually there are screws, clips or levers on the bottom of the vacuum and you need to either remove the bottom plate and once you have taken the screws, etc. out the top cover will come off. And then you can proceed with the removal and the install of the new belt. 1st you need to remove @ least one end of the Hoover brushroll and take of the old belt and slide on a new belt. Once the belt is on the pulley side of the brushroll; then re-install the brushroll. Make sure that the brush is spinning freely B4 you install the new belt, then take a belt puller or a screwdriver with a left or right hand hook to use as a belt puller and then stretch the belt onto the motor pulley, then take and roll the belt until it is tracking straight and then re-install the top cover and or the bottom plate, tighten down the screws, levers or clips. So, please feel free to contact your local vacuum cleaner dealer in your area or in the yellow pages, or contact the factory phone number or website to further assist you with your questions.
http://www.hoover.com Telephone
Contact our Customer Service Department at 1.330.499.9499
Monday through Friday
8 a.m. - 7 p.m. EST
Thanks, Don the Vac Man
Go Ahead. Use Us.