Mercury - Low Oil Switch 2-Stroke Outboards & Jet Drive OEM Precision 856156T02. Overview. When you're out on the water, every sound and signal matters - and knowing your engine's oil level is one of the most important. The Quicksilver 856156T02 Low Oil Switch gives you that peace of mind. Designed for select Mercury and Mariner 2-Stroke outboards and the 200HP OptiMax Jet Drive, this switch keeps constant watch over your oil reservoir and alerts you when it's time to refill. It's a small compon