Mercury - Oil Pressure Gauge L-H Engine Protection Monitoring Black Face Black Bezel 79-8M6020036. OverviewThis oil pressure gauge gives you a steady look at how the engine's lubrication system is holding up while you're running. The needle settles into a smooth sweep, so any drop or spike stands out right away without forcing you to stare at the panel. Out on the water, it reacts naturally as you throttle up, idle down, or run through chop. It's a simple tool that quickly becomes part of your r