A broken saw blade, failed drive belt or damaged rubber tire can prevent the blade from moving when the motor runs.
Check the condition of the blade and replace the blade if it's broken. If the blade is okay, examine the rubber tires and replace any worn or damaged tire. If the blade and rubber tires are okay, check the motor drive belt and replace if it's worn or broken.
These repairs may help solve your band saw problem
Replace the band saw drive belt
The drive belt connects the drive motor pulley to the lower wheel and rotates the lower wheel, which spins the band saw blade. Examine the drive belt regularly and replace the drive belt if it's broken or damaged.
If your band saw blade isn't moving but you hear the motor running, the drive belt could be broken. This step-by-step repair guide and video show how to replace a band saw drive belt in just 15 minutes.
The band saw blade becomes dull with use. Cutting hard wood or metal hastens blade dulling. The band saw blade is dull when you must apply significantly more than normal force to push the piece you're cutting through the blade. Replace the band saw blade when it's dull or damaged.