- Taking the self-propelling system on a lawn mower involves reaching into the engine. Since accidents can happen, the operator needs to follow safety precautions before doing anything. To prevent accidental start-ups, move the ignition switch firmly into the “Off” position and, if applicable, take the ignition key out. For further protection, unhook the rubber boot from the tip of the spark plug on the front of the engine, and always wear work gloves during this process.
- The self-propelling system on a lawn mower operates through a few simple machines. On the underside of the engine, the crankshaft sticks out slightly. Connected to this shaft is a pulley and, attached to the outer rim of the pulley, is a drive belt. This drive belt runs up to the front of the mower where it connects to another pulley, which in turn, connects to the front axle. When the crankshaft spins, the rear pulley starts spinning and the belt transfers power to the wheels.
- In order to disconnect the self-propelling system on a lawn mower, the operator will need to gain access to the drive belt. Since this belt sits below the main engine block, it is difficult to access. A cover may sit atop and wrap around the drive system or it may sit directly underneath the engine block. In most cases, the engine won’t need to be removed to access this belt. If engine removal is required for your model, allow a professional to take it off for you.
- To disconnect the drive system on a self-propelled lawn mower, the operator will need to take the belt off the two pulleys so power no longer transfers to the front wheels. On most models, a spring loaded clip connected to a lever allows the operator to put tension on the belt to engage the drive system. Disconnect this spring lever. When removing the belt, pull firmly downward on the belt while rolling the pulley with your gloved hand. When reinstalling the belt, route it in the proper direction.