Thermostat For Yamaha 2 Stroke 9.9 15 25 30 40 55 HP Outboard 6F5-12411 18-3625

Thermostat for Yamaha 2-Stroke Outboard

This thermostat for Yamaha 2-stroke outboard motors regulates engine temperature and matches OEM cross-reference numbers 6F5-12411 and 18-3625.

Overview

This thermostat for Yamaha 2-stroke outboard cooling systems is a replacement part designed to maintain proper operating temperature. Designed for Yamaha 9.9, 15, 25, 30, 40, and 55 HP two-stroke outboards, it helps prevent overheating by controlling coolant flow. The 6F5-12411 and 18-3625 references allow straightforward identification of this thermostat for Yamaha outboard service.

Built For Performance

• Replacement thermostat for Yamaha 2-stroke outboard cooling systems
• Cross-references OEM part numbers 6F5-12411 and 18-3625
• Constructed to match factory thermal opening specifications
• Helps regulate coolant flow to prevent overheating or overcooling
• Direct fit for listed Yamaha outboard horsepower ratings

Fits These Machines

• for Yamaha 9.9 HP 2-stroke outboard
• for Yamaha 15 HP 2-stroke outboard
• for Yamaha 25 HP 2-stroke outboard
• for Yamaha 30 HP 2-stroke outboard
• for Yamaha 40 HP 2-stroke outboard
• for Yamaha 55 HP 2-stroke outboard

On-The-Job Use

• Used during routine outboard cooling system maintenance
• Commonly replaced when engine runs hot or cooling performance drops
• Works for freshwater and saltwater outboard operation
• Suitable for fishing boats, utility craft, and auxiliary power

Specs At A Glance

Good To Know

Q: Is this a factory original part? A: No, this is a replacement thermostat built for Yamaha outboards. Confirm your engine serial number and part number before ordering.

Q: What does this thermostat do? A: It opens and closes to regulate coolant flow, helping the outboard reach and maintain operating temperature. Replacing a worn thermostat can restore cooling performance.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.