The John Deere 160 riding lawnmower uses a double blade mowing deck for cutting grass. The blades spin due to a series of pulleys mounted to the topside of the mower deck. The pulleys have a serpentine belt that attaches to a drive pulley mounted to the bottom of the engine. As the belt ages, it starts to dry rot and eventually slips. When this happens, you must replace the belt with a new one.
Place wooden blocks under each side of the mower deck, then lower the mower deck onto the blocks. This takes tension off the linkage rods that hold the mower deck onto the undercarriage of the mower.
Remove the cotter pins from the linkage pins, then pull the linkage pins out of the linkage rods. Rotate the linkage rods downward.
Pull the drive belt off the pulley on the bottom of the engine, remove the block from under the deck and slide the mower deck out from under the mower.
Pull the belt off the pulley system on the mower deck. Make sure you write down a diagram of how the belt routes around the pulleys.
Place the new belt around the pulleys. Follow the diagram you drew to ensure you install the belt correctly. If you do not, the blades will not rotate properly.
Slide the mower back under the mower deck, then place it back onto the blocks.
Place the belt over the drive pulley on the bottom of the engine.
Rotate the linkage bars upward, slide the linkage pins in place and secure them with the cotter pins.