BMW 11221252206 Flywheel

If the teeth of the starter ring gear are badly worn, the ring gear will need to be renewed on a flywheel or the complete driveplate replaced on an automatic transmission unit. To remove the ring gear from a flywheel, drill a hole 6.0 mm in diameter at the root of one tooth, ensuring not to drill all the way through, with a depth of 8.0 mm being sufficient. Split the ring with a sharp cold chisel. Heat the new ring gear in an oil bath or electric oven to a temperature between 400 and 450° F (200 and 230°C). Place the ring on the flywheel with the chamfer facing the engine and tap it squarely into position using a brass drift. If the machined face of the flywheel is scored or shows surface cracks, it should be surface ground, but the thickness of the driven plate contact area of the flywheel must never be reduced below 0.535 in (13.6 mm).