When the front-wheel drive on your Toro lawn mower malfunctions, you may find that the front wheels are stuck fast and refuse to budge or may simply roll forward, depending on you to push the mower, instead of simply guiding it along. Either way, its crucial that you diagnose the problem and repair the feature that was probably part of the reason you bought the mower in the first place.
Since the self-propelled Toro mower relies on a belt to turn the wheels, the first place to look when you have a loss of drive is the belt itself. The belt may be torn, worn and slipping, broken and completely off the machine or may have stretched over time to the point where it doesn't control the wheels as it should. Examine the belt to determine whether it is worn or frayed. Look for missing chunks of rubber or variation in the width of the belt along its length. If the belt appears damaged, replace it with the appropriate Toro belt for your model of mower.
While all mowers accumulate a certain amount of debris on the underside of the deck and around the wheels, a mower that hasn't been cleaned in ages can suffer malfunctions. Check the wheels and the belt to ensure that debris isn't the cause of front-wheel drive problems. Over time, grass clippings harden and may interfere with the workings of the self-propulsion feature. With the spark plug disconnected, turn the mower over and clean out grass clippings, twigs or rocks that may have become lodged in the mower's wheels and belt system.
Drive Cable Malfunction
Since the self-propelled mower with front-wheel drive depends on the self-propel drive cable to control it, a problem with the cable can cause the wheels to malfunction. Whether you've just installed a new cable or suspect that your old one is out of adjustment, it's a quick fix. Loosen the cable support nut that's located on the side of the mower's handle. Pull the cable's jacket toward the mower's engine until the cable is taut and displays no slack. Tighten the cable support nut back into place to hold the adjustment you've just made.
If you're new to using a Toro mower with front-wheel drive, it's possible you may not be operating the mower properly. Self-propelled Toro mowers have two separate bars on the handle. The one atop the handle is the blade-control bar and must be held in place when you pull the starter recoil handle to start the machine. Once the machine's engine is running, squeeze the self-propel drive bar, located underneath the handle, toward the handle and hold it there to operate the self-propulsion feature. To disengage the front-wheel drive, simply release the self-propel drive bar. To stop the blades from turning and to kill the engine, release the blade-control bar.