Sierra 18-7954-1 Oil Filter Sierra replacement canister oil filter for Yamaha Outboards. Sierra oil filters are designed to be an exact fit and performance replacement for your current OEM canister filter. Sierra recommends replacing your oil filter ever 50 hours of operation or at a minimum of once per year, preferably at winterization. Anti-Drain-Back Valve Engineered with premium grade materials that will excel in the extreme marine environment Epoxy coated for corrosion resistance Heavy-wall