Cant get blades to full RPM replaced all idlers all belts greased spindles new elec. clutch new blades when cutting grass it leave rows of uncut grass

SOURCE: I have a Craftsman Lawn tractor. Blade leaves grass uncut.

Hi Tom,
Check your spindle shafts for loose play. If your bearings are worn out and sloppy, the belts pull the spindle to one side and an angle cut results... close cut grass at outer edge and high in center will leave this grass trail you are describing. I'd replace the bearings next year for sure.
I hope this helps... Good luck!

Jeffery Lewis

• 329 Answers
• Posted on May 23, 2011

SOURCE: Craftsman DGS6500 with 54" precision

The only thing that makes sence is that some how te blades are the wrong ones they are not long enough . raise the tractor up set the blades so they are in line with each other they should not have more then a 1/4 inch gap if it's more you have the wrong blades.

SOURCE: A row of uncut grass left between blaces when mowing

THE answer that FINALLY worked for me. Torque the bolt that holds on the blade to the recommended torque specified in your owners manual (for my Exmark this torque is 120 ft-lbs). When I first used the torque wrench, i was quite surprised by the amount of addional force I needed to apply to reach 120 ft-lbs Exmark blades have a round blade hole with a washer and therefore, relies only on friction provided by torquing bolt to the proper torque to prevent slippage so that the blade rotates at the same speed as the spindle. When slippage between the blade and spindle occurs, blade tip speed slows leaving uncut grass.
Note: this solution will NOT work for mowers with a blade and spindle design which uses a positive means (e.g., a star shaped hole on the blade) that assures the blade rotates at the same speed as the spindle with no slippage.