When I engage the pto switch, it kicks on and the clutch is running fine too. My problem is that the belts do nothing, they do not turn.When I take the deck off, the belts seem tight, but when I put the deck back and put on the pto belt, it seems to have slack in it. Could this belt be bad? How can I tell? I cannot figure what could be causing the belt not to turn.Please help. Thank you for your help.