Briggs & Stratton 491657S Engine Switch-Oil Pressure

The Briggs & Stratton 491657S Engine Switch-Oil Pressure operates as an electrical safety device that responds to engine lubrication conditions by opening or closing an internal contact system based on oil pressure levels, and allowing the engine control system to monitor whether sufficient pressure is present during operation. When oil pressure drops below a calibrated threshold, the switch changes state to trigger an indicator or shutoff signal within the ignition or warning system, interrupting normal operation logic. In engine assemblies, this component is usually installed on the crankcase, or oil gallery port of compatible engines, where it directly interfaces with internal oil flow passages for pressure sensing.