Thermostat – Fits Yamaha 150HP, 175HP, 200HP Outboards (Replaces 6DA-12411-01-00, 6DA-12411-00-00)

Thermostat – Fits Yamaha 150HP, 175HP, 200HP Outboards

This thermostat is designed for Yamaha 4-Stroke 150HP, 175HP, and 200HP outboard motors from 2012–2018, including the F150, F175, F200, VF150, and VF175 series. It regulates engine temperature to a consistent 60°C (140°F) for optimal performance and fuel efficiency.

Engineered as a direct replacement for original Yamaha parts, this component ensures a precise fit and reliable function within the engine's cooling system.

• Operating Temperature: 60°C (140°F)
• Installation: Direct OEM replacement fit
• Construction: Features a high-grade, corrosion-resistant housing

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Technical Specifications

Package Contents

1 x Thermostat (Replaces 6DA-12411-01-00)

Installation Guide

1. Safety First: Ensure the engine is completely cool and the battery is disconnected before beginning.
2. Locate Thermostat Housing: Find the thermostat housing on the engine block, typically connected to the main coolant hoses.
3. Remove Housing Cover: Loosen and remove the bolts securing the thermostat housing cover. Note their positions if they are different lengths.
4. Extract Old Thermostat: Carefully remove the old thermostat and the gasket or O-ring. Note its orientation.
5. Clean Surfaces: Thoroughly clean the mounting surfaces of the housing and cover, removing all old gasket material and corrosion.
6. Install New Thermostat: Place the new thermostat into the housing in the same orientation as the original.
7. Install New Gasket: Fit a new gasket or seal onto the housing. It is highly recommended to use a new gasket to prevent leaks.
8. Re-secure Cover: Replace the housing cover and tighten the bolts evenly in a crisscross pattern to the manufacturer's torque specifications.
9. Reconnect Components: Reattach any hoses and reconnect the battery.
10. Test for Leaks: Start the engine and let it warm up, checking carefully for any coolant leaks around the thermostat housing.

Troubleshooting & FAQ

Q: How can I confirm this thermostat fits my specific engine model?
A: Check your engine model and year against our compatibility table. You can also use our Yamaha Serial Number Guide to verify your engine details and cross-reference the OEM part numbers (6DA-12411-01-00, 6DA-12411-00-00) with your service manual.

Q: What are the signs of a failing thermostat?
A: Common symptoms include engine overheating, the engine taking too long to reach operating temperature, or erratic temperature gauge readings. An overheating engine can cause serious damage, so timely replacement is critical.

Q: What is the operating temperature of this thermostat?
A: This thermostat is designed to open at 60°C (140°F), ensuring your engine maintains the correct temperature for efficient operation.

Q: How often should I replace my outboard's thermostat?
A: As a preventative maintenance item, it is good practice to inspect and consider replacing the thermostat every 200-300 hours or every 2-3 years, especially if operating in saltwater. Always refer to your engine's service manual for specific recommendations.

Q: OEM vs. Aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.