My spin brushes will no work. Have replaced and cleaned screen and brushes are turned on

The brushes are turned by a motor. No belt. It's possible the gears on the brushes have a flat spot on them which would stop them from turning under a load.

Follow these steps if the Brushes Fail to Spin
•If the brushes on your Hoover carpet cleaner fail to spin, there may be a problem---some sort of blockage---with the suction or with the belt that turns the brushes.
Turn the Hoover carpet cleaner over, and inspect the brush area. Debris, strings, or pet hair may be tangled in the rollers, keeping them from turning. Use a pair of scissors to cut away any obstructions in this area. Flip the Hoover carpet cleaner back over, and turn it on to see if cleaning the rollers has solved the problem.
To check the belt, turn the Hoover carpet cleaner over, and remove the bottom plate screw with a Phillips head screwdriver. Investigate the belt area to see if it is broken or has somehow slipped off. If it is broken, you can order a part from Hoover.com or from many of the other online parts stores.
When the belt arrives, simply slide it on in place of the broken belt, reattach the bottom plate and turn the Hoover carpet cleaner right-side up. Turn it on to test your solution.

The brushes turn by the airflow from the vacuum suction turning a turbine motor to spin the brushes. First try to spin the brushes by hand. If they won't turn it usually means the brushes are clogged with hair and debris or need replaced or the turbine could be seized up. If the brushes won't spin reach under the brushes and push the little tabs and remove the brush block asssembly from the machine. If the brushes spin freely after you remove them from the machine then that means that most likely the turbine is seized and will need to be repaced. If the turbine is not seized you may simply just have a clogged filter screen. Most steam vacs have a red screen filter either on top or underneath the machine. On the top it is under a little clear plastic cover that you have to pry off before you can pull the screen out to clean it. If it's underneath you can pull it out and clean it.

First, please be sure to unplug your Steam Vac and remove both the clean water and the dirty water tank.
There should be a square stem that sticks up in the center of your brush assembly. If this stem is broken you will need to replace the complete brush assembly. If the stem is good; turn your cleaner on it's side and check in the area where the brush assembly goes (with the brush assembly removed). In the center of this area there is a square hole where the stem from the brush assembly goes. The square hole is in the bottom of the turbnie that spins your brushes. Using a large flat blade screw driver (not so large that you'll damage the hole), stick it in to the square hole and try to spin it. It should spin freely, if it is very hard to spin or won't spin at all, your turbine is bad and will need to be replaced.
Hoover part number for brush assembly:48437022
Hoover part number for turbine: 43191008

On mine there is an air turbine that powers the brushes. There is a red screen that you squeeze and pull out to clean. Perhaps yours is clogged. If the screen is clear, perhaps the turbine has something binding it to keep it from turning. I hope this gets you on the path to repair your problem.

I have the SteamVac Dual and there's a screen on the underside of the unit. It's beneath the brushes and it's red. You have to pull and wiggle it to get it out. With the machine unplugged, lay the unit with the handle on the floor. In the owner's manual ( http://www.hoover.com/pdfs/manuals/F7222900.pdf ) this is shown on page 10 figure 3-2. Clean that screen.
If they still won't spin, then take the brushes out. Again, with the unit on the floor, you simply grab the unit firmly and pull towards you. It's much easier to remove than the screen. I took the brush unit outside and blasted it with the house. You'll have to pull out whatever fur balls are clogging it but eventually you'll see that the brushes spin freely with the water squirting on them. Plug the brush unit back in and - in my case - they started spinning.

Have you checked the lint screen? Your brushes are air driven if it's a Hoover Spin Scrub. There is a clear cover on the left side, when facinf from front. Remove this cover, about 3x5 inches and tapered, and clean the screen. Some units have a red or white screen that you can pull out from the bottom of the unit, left side just behind the brush block. Clean the screen then reinstall. Check that recovery tank is properly positioned- lack of seal means less suction which translates to brush block not turning.

i had the same prob. i contacted i-robot and was told the motor that turns the brush is shot. there is no replacement part. they offered to replace my i-robot with a new one from the 400 series. at about 60% of a new one. that's the only option that i know of.

THE TURBINE WHICH DRIVES THE BRUSHES RUNS OFF SUCTION, A POOR DESIGN IN MY OPINOIN THEY GO BAD ON A REGULAR BASES. PROBABLY HAVE TO REPLACE TURBINE ASSEMBLY

Is the shaft still on the brush block, if it broke off, then replace the block. if it is ok, then the turbine(#13) is most likely the problem. It is what drives the brushs. You may be able to take the turbine apart and clean it, if that doesn't work the replace it.