OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Removing drive roller from SB 590

You should be able to see where it is slipping, since the slip rate is so high. You can see the engine pulley turn, and you can see whether the reel and roller pulleys turn. Either the belt is slipping or the roller clutch is. If the belt is slipping, with full movement rearward on the lever clutch, you need a new belt.

From the picture, it looks as if the belt may be bottoming in the engine pulley. If it is bottoming you should be able to see that the bottom of the pulley is shiny, and probably the bottom of the belt too. Worn belts bottom in pulleys, and they can't drive that way, they have to wedge in the V of the pulley.

You can also see in the picture that with the clutch lever all the way back, the tensioning spring is not stretched, so there is just about no tension on the belt. That can only happen if the belt is worn or stretched.