Removal of a Briggs & Stratton flywheel may be necessary on newer engines when the drive key has become damaged, and on older engines for that reason or to replace the ignition points and condenser. This is a task easily within reach of most mechanically inclined people and requires few tools.
To remove a Briggs & Stratton flywheel you will need a small socket set, a hammer, a block of wood and a flywheel puller. A steering wheel puller from your local auto parts store will work just fine as a flywheel puller. A small magnet is helpful, but not required.
To remove the flywheel you must first remove the recoil starter and the flywheel cover. Do both in one step by removing the three or four bolts--it varies by engine model--and attaching the cover to the engine. The cover will lift straight away from the flywheel when the bolts are removed. You may also need to remove the gas tank on some engines.
After removal of the cover the recoil starter one-way clutch must be removed. Look for a retaining ring at the base of the square shaft in the center of the flywheel and remove this ring if it is present. Not all engines use a retainer. After removing the retaining ring (if it was used on your engine) pull the square piece off the crankshaft. Remove the steel balls, which are now exposed. Using a magnet will make this step easier.
Place a small block of wood against one of the tabs on the clutch basket and strike with a hammer to turn the clutch basket in a counter-clockwise direction. It should turn off by hand after initially loosening it with a hammer blow.
The large nut under the clutch basket must be removed to pull the flywheel. While firmly holding the flywheel turn the nut counter-clockwise to remove it.
Install the flywheel puller by threading the two puller bolts in to the holes in the face of the flywheel. Tightening these bolts evenly is important for a straight pull with the puller. Turn the large center bolt against the crankshaft end to pull the flywheel off.
Occasionally the flywheel is stuck on the crankshaft. Should this happen a hammer tap on the top of the center puller bolt may jar it loose. The application of limited amounts of heat, such as from a small torch or heat gun, may also help free a stuck flywheel. Use heat with care as too much may damage the flywheel or engine wiring.