Yamaha - Oil Tank Harness 26FT Electrical Oil System Component 6R3-85721-80-00. Overview. This is one of those rigging pieces that either works perfectly or causes headaches fast. I've dealt with oil systems throwing alarms just because of a bad harness run or weak connection. When this line is solid, your oil tank and engine stay in sync and you don't have to second guess what the system is telling you. It's a behind-the-scenes part, but it matters every time you turn the key.. Key Features. • Extended 26-Foot Length - Gives you the reach needed for clean routing in larger or more complex boat layouts.• Stable System Communication - Maintains consistent signal between oil tank and engine monitoring system.• OEM Connector Design - Built to match factory plugs for secure, no-hassle connections.• Marine-Grade Durability - Holds up against moisture, vibration, and long-term use in harsh conditions.. Engine & Boat Compatibility. Designed for Yamaha outboard engines with remote oil tank sys