Question on older dirt devil uprights...

[icee]

I've aquired a few older dirt devil uprights, and even on my very short carpet it seems to give the rollar brush trouble. It seems like unless I'm pulling the sweeper back, the brush won't spin. But if I tilt the sweeper off the floor it spins freely with no issue. No belt squeel either. Any idea what could be up? Neother of them have height adjusters

 

[vacuumlad1650]

Worn belt most likely

 

[icee]

Vacuumlad1650

Thanks bub, I just figured it didn't hurt to ask to make sure!