804295T Mercury Thermosensor | Genuine Used Part

🔧 Product Description

Genuine Mercury Four-Stroke Engine Temperature Sensor - Part Number: 804295T

A genuine used Mercury Marine engine-temperature sensor for selected Yamaha-derived 75HP, 80HP, 90HP, 100HP and 115HP four-stroke outboard motors.

The sensor measures engine or cooling-system temperature and sends a variable signal to the engine control or warning system.

⚙️ Key Features

• Genuine used Mercury Marine thermosensor
• Correct OEM part number 804295T
• Yamaha cross-reference 67F-85790-00-00
• Fits selected Yamaha-derived Mercury four-stroke engines
• Variable-resistance temperature sensor rather than a simple overheat switch

🚤 Compatibility

Commonly used on

• Yamaha-derived Mercury and Mariner four-stroke cooling systems
• Carburetted and selected EFI engine-management systems

Typically suits

• Engine models:
• Mercury / Mariner 75HP four-stroke
• Mercury / Mariner 80HP four-stroke
• Mercury / Mariner 90HP four-stroke
• Mercury / Mariner 100HP four-stroke
• Mercury / Mariner 115HP four-stroke
• Production groups from approximately 2000-2006 using thermosensor 804295T
• HP Range: 75HP - 115HP
• Engine Type: Mercury / Mariner Yamaha-derived inline four-cylinder four-stroke outboard
• Year Range: Approximately 2000-2006

🔌 Function

The sensor changes resistance according to engine temperature. The engine-management and warning systems use this signal for temperature monitoring, fuel compensation and overheat protection.

⚠️ Common Signs of Failure

• Temperature warning activates with a cold engine
• Overheat protection does not operate
• Temperature reading is fixed or erratic
• Engine runs excessively rich during warm-up
• Temperature-related diagnostic code is stored
• Sensor resistance is outside specification
• Connector or harness movement changes the reading

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 804295T current Mercury thermosensor reference

OEM / Related Numbers

• 804295T
• 804295
• 67F-85790-00-00 Yamaha cross-reference
• 67F857900000
• 804296 related sensor retainer
• 27-8042971 related sensor gasket or seal
• Related engine wiring harness and temperature-warning circuit

Aftermarket / Verified Equivalents

• Engineroom: M9586 - replacement thermosensor
• Aftermarket direct replacement under Mercury 804295T
• Aftermarket direct replacement under Yamaha 67F-85790-00-00

📦 Condition

• Genuine used part
• Removed from running engine where applicable
• In good working condition unless otherwise stated