Power off the MTD Yard Machine rototill. Find the spark plug on the right side of the Yard Machine's Briggs & Stratton engine and pull the tin, black ignition wire from its rear as a safety precaution.
Check the fuel level in your rototill's gas tank. Insert more fuel if necessary. Replace gas within the tank if it is old and has been left over from last season by siphoning out the old gas using a plastic hose and storing it in a handheld gas canister. Insert fresh gas.
Remove stones and debris from the blades, or tines, along your rototiller. Use a cloth to carefully clean along the blades and remove mud or buildup that can affect the operation of the tines.
Wiggle the individual tines and check for looseness. Use a socket wrench to tighten the bolts holding the tine in place if the tines are loose. Twist the bolts clockwise with your wrench to properly tighten them.
Position a pan under the carburetor on the left side of the rototill's mower. Loosen the nut on the bottom of the carburetor bowl using your wrench. Wait as the excess fluids leak out of the carburetor and into the pan.