Mercury – Diesel Engine Unswitched Power Harness 25 Foot | Constant Power Harness | 84-8M0150524

The Mercury Diesel Engine Unswitched Power Harness (25 ft) is designed for large diesel vessels where batteries or power distribution points are mounted far from the engine. It delivers continuous, constant battery power without relying on ignition-switched circuits, ensuring critical engine and support systems remain energized at all times.

The 25-foot length supports extended routing through large engine rooms and hull layouts without splicing, extensions, or tight bends. OEM Mercury construction helps maintain stable voltage delivery, protect connector integrity, and support long-term electrical reliability in demanding marine diesel environments.

Key Features

• Unswitched Power Circuit – Provides constant battery power regardless of ignition position
• 25-Foot Length – Designed for long-distance diesel electrical routing
• Diesel-Specific Electrical Design – Sized to meet Mercury diesel system power demands
• OEM Mercury Construction – Marine-grade wiring and sealed connectors for durability

Engine & Boat Compatibility

• Mercury diesel engines
• Mechanical control systems
• DTS (Digital Throttle & Shift) control systems

Important Notes

• Supplies constant (unswitched) power and remains live even when the engine is off.
• Intended for large vessels with extended electrical runs.
• Proper routing helps reduce connector strain and prevent chafing.

FAQs

1) What is an unswitched diesel power harness used for?
It provides continuous battery power to diesel engine systems or components that must remain powered at all times.

2) When should I choose the 25-foot harness?
It’s recommended when batteries or power distribution points are located far from the engine and shorter harnesses would require splicing or extensions.

3) Does this harness work with DTS systems?
Yes. It is compatible with Mercury diesel engines using both mechanical and DTS control systems.

4) Does this harness turn off with the engine?
No. This is an unswitched harness and remains powered even when the engine is not running.

5) Why choose an OEM Mercury harness for long diesel runs?
OEM harnesses use the correct wire gauge, sealed connectors, and marine-grade insulation to prevent voltage drop, corrosion, and long-term electrical issues.