6D3-12411-00-00 Thermostat 140°F for Yamaha AR 250 1800 2021-2023

Thermostat for Yamaha AR 250 1800

This thermostat replaces OEM part 6D3-12411-00-00 and regulates engine coolant temperature at 140°F on Yamaha AR 250 1800 watercraft from 2021 through 2023.

Overview

This thermostat is a direct replacement for OEM part 6D3-12411-00-00, engineered to regulate coolant flow at a 140°F opening point on Yamaha AR 250 1800 models built between 2021 and 2023. It keeps the engine operating within its designed temperature range, protecting against overheating during high-load operation and ensuring consistent performance from cold start through full throttle. Ideal for routine maintenance or replacement of a stuck or failed thermostat.

Built For Performance

• 140°F opening temperature for proper coolant regulation
• OEM cross-reference 6D3-12411-00-00 for direct fitment
• Precision-machined valve for consistent opening and closing
• Corrosion-resistant construction for marine environments
• Engineered to maintain stable operating temperature under load

Fits These Machines

• for Yamaha AR 250 1800, 2021-2023

On-The-Job Use

• Routine cooling system maintenance
• Replacing a stuck or failed thermostat
• Overheating diagnosis and repair
• Seasonal pre-launch engine servicing

Specs At A Glance

Good To Know

Q: How do I know if my thermostat needs replacing? A: Common signs include the engine running too hot or too cold, inconsistent temperature readings, or coolant not circulating properly. Replacing it at the first sign of trouble prevents overheating damage.

Q: Does this thermostat fit my specific model year? A: This thermostat is designed for Yamaha AR 250 1800 models from 2021 through 2023, matching OEM part 6D3-12411-00-00. Always confirm your serial number and existing part number before ordering.

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