This V-belt transmits drive torque from the engine to the threshing rotor and associated cleaning components. It sits in the threshing-drive position, connecting the main pulley to the rotor input shaft. The belt has four ribs that engage with matching grooves on the pulleys to prevent slip under load. A worn belt will cause a loss of rotor speed, leading to incomplete threshing and increased grain loss. The manufacturer matches the original belt’s pitch length and cross-section so that tensioner travel remains within the specified range. On installation, ensure the belt is fully seated in all pulley grooves and adjust tension to the service-manual specification.