The mowing blades on Rally lawn tractors are powered by a belt attached to the engine that loops around a series of round pulleys. After a few seasons of hard mowing, the belt can become cracked or worn. Murray, the company that builds Rally lawn tractors, recommends checking the deck belt on an annual basis. Changing the deck belt requires few tools and can be done in under 30 minutes.
Park the tractor on a level area and disable it from starting by detaching the sparkplug wire and removing the ignition key. Push the mower deck lever forward so the deck is in its lowest position.
Remove the cottar pins and washers from the adjuster arms, located on the side of the tractor chassis, just above the mower deck. Pull the mower deck off of the hanger near the axle. Twist off the mower drive belt from the stack pulley and slide the mower deck to the right side of the tractor.
Remove and discard the old mower drive belt. It can be twisted off the pulleys or simply cut and then pulled away from the mower deck.
Following the same route of the belt that was just removed, thread the replacement belt around the pulleys. Loop it first around the right mandrel pulley, then the left mandrel pulley and the idler pulley. Route the belt around the tractor engine pulley.
Attach the mowing deck to the tractor in the reverse order of steps used to detach it.
Wear sturdy gloves to avoid getting cut by sharp metal.