The number 0311598 (or simply 311598) is a part number for a Gearcase Fill and Drain Screw Washer, a critical maintenance component for marine outboard motors and sterndrives.
Primary Reference: Marine Drain Plug Washer This washer is a standard "change-out" item that should be replaced every time you change your gearcase oil to prevent water intrusion or oil leaks.
Brands: Primarily used for Johnson, Evinrude, OMC, and BRP (Bombardier Recreational Products) engines. Material: Typically made of high-quality nylon to ensure a durable, leak-proof seal. Dimensions: Designed to fit drain and fill screws with 10mm threads. Compatibility: Outboards: Fits a wide range of models from 1973 through 2006, including 20–300 HP engines. Sterndrives: Compatible with various OMC Cobra and Volvo Penta (SX, DP series) models.
