The Briggs & Stratton 691457 Lawn Mower Crankshaft helps transfer engine power by converting piston movement into rotational motion. This essential component works with the engine’s internal parts to support proper operation and mechanical performance. Replacing a worn or damaged crankshaft can help restore engine function during repairs and maintenance. Check your lawn mower’s engine... https://www.wholetoolbox.com/briggs-stratton-691457-lawn-mower-crankshaft/691457.html