Yamaha - 10W30 Marine Full Synthetic Oil - Quart - QBL-10W30-FS-12 - 6 Pack. Protect your Yamaha outboard with a full synthetic marine oil engineered for real on-the-water conditions. Yamaha 10W30 Marine Full Synthetic Oil helps maintain consistent lubrication under heat and load, supports cleaner engine operation, and provides added corrosion protection for humid and saltwater environments. It's a reliable choice for routine maintenance when you want smooth performance and dependable protection from start-up through shut-down.. Key Features. Viscosity: 10W-30. Type: Marine full synthetic outboard engine oil. Formulated to help protect against wear during high RPM operation. Helps resist thermal breakdown in high-temperature conditions. Marine-grade corrosion protection for storage and downtime. Supports cleaner internals by helping reduce sludge and deposits. Bottle Size: 1 quart (6 Pack). OEM Part Number: QBL-10W30-FS-12. Yamalube 10W-30 full synthetic is recommended for use on all o