12 Faults and remedies 12.5 Threshing mechanism 67088 12.5 Threshing mechanism 87900 12.5.1 Threshing mechanism problem and remedy Observe the general warnings at the beginning of the "Trouble and remedy" chapter. 250 00 0293 210 2 - BA DOMINATOR 150/140/130 - 12/09 Malfunction Cause, remedy Threshing mechanism Dirty threshing parts cause unbalance and grain losses and worn threshing parts reduce combine throughput and leave unthreshed grain heads. Drum wrapping up • Observe even material flow from the cutterbar! • Position intake auger lower. • Have the feeder chain slip clutch adjusted. • Decrease concave-to-drum clearance. • Increase drum speed in damp crops.
• Drive more slowly as moisture increases. • Correct basic adjustment of concave. • Clean and grease the threshing drum variable- speed drive (belt slippage). • Check low-pressure hydraulic system and smooth movements of threshing mechanism drive belt ten- sioner cylinder with jockey pulley. Machine speed varies heavily. • Check and/or adjust main drive V-belt clutch. • Check engine (see engine problems). Stones and other foreign objects damage the threshing mechanism. • Clear stone trap regularly. • Do not cut unnecessarily low on stony ground. High V-belt wear • Adjust the V-belt tensioning device properly. • Derust and clean the V-belt pulley contact faces.
• Clean and grease sliding faces of variable speed pulleys. • Clean oily belts with soapy solution. Poor threshing action • Decrease concave-to-drum clearance. • Increase the threshing drum speed. • Install disawner bars. • Correct basic adjustment of concave. • Have worn and/or damaged threshing mechanisms repaired (concave, threshing drum bars). • If necessary use special threshing equipment. Insufficient disawning • Decrease concave-to-drum clearance. • Increase drum speed. • Install disawner bars. • Wait for crop to ripen for some more time. • Correct basic adjustment of concave. • Check concave and threshing drum bars for wear and damage.