I have a 42' yard machine riding mower I have sharpened the blades and after I put them back on and tried to engage the blades the drive belt started smoking. I think I tightened the blade nut too tight and the blades won't rotate. Does anyone know what the proper torque is for this? Any help would be appreciated. Thanks

Did you happen to lose the blade adapter from the bottom side of the spindle assembly? It goes between the spindle assembly and the blade.

Neither blade had an adapter or spacer. They have a star type pattern notch's cut out on the blade and it slips up on and then I put the nut on and tightened them down. I think too tight because I tried to rotate them by hand it they were hard to turn. I didn't want to loosen them for fear of them coming off. Thanks

The torque on the blade nut will not affect the spindle turning. Check to make sure the brake on the blade spindle is releasing when you engage the blade lever. Also check the spindle bearings for binding and make sure your belt is routed the correct way.

Neither blade had an adapter or spacer. They have a star type pattern notch's cut out on the blade and it slips up on and then I put the nut on and tightened them down. I think too tight because I tried to rotate them by hand it they were hard to turn. I didn't want to loosen them for fear of them coming off. thanks

Okay, let me back up a little here. The star shape aligns with the star shape on the spindle assembly. If you are not aligned you could be causing the blade to bind against the housing.