Thermostat – Fits Yamaha 75-90HP 4-Stroke Outboards (Replaces 6FP-12411-00-00)

Thermostat – Fits Yamaha 75-90HP 4-Stroke Outboards (Replaces 6FP-12411-00-00)Thermostat Fits Yamaha 75 90HP 4 Stroke Outboards (Replaces 6FP 12411 00 00) This replacement thermostat is engineered to fit Yamaha F75B, F90B, and VF90A 4 cylinder outboard engines manufactured between 2016 and 2022. It ensures your engine maintains the correct operating temperature for optimal performance and longevity. It serves as a direct replacement for Yamaha part number 6FP 12411 00 00 and other aftermarket equivalents, offering a precise fit

Thermostat – Fits Yamaha 75-90HP 4-Stroke Outboards (Replaces 6FP-12411-00-00)

This replacement thermostat is engineered to fit Yamaha F75B, F90B, and VF90A 4-cylinder outboard engines manufactured between 2016 and 2022. It ensures your engine maintains the correct operating temperature for optimal performance and longevity.

It serves as a direct replacement for Yamaha part number 6FP-12411-00-00 and other aftermarket equivalents, offering a precise fit and reliable function.

• Operating Temperature: 60°C (140°F)
• Installation: Drop-in direct replacement
• Housing Material: High-quality brass for corrosion resistance

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 (6FP-12411-00-00)

Installation Guide

1. Disconnect Battery: Ensure the engine is off and disconnect the negative battery cable for safety.
2. Locate Housing: Find the thermostat housing on the engine block. It is typically a small dome-shaped cover with a coolant hose attached.
3. Drain Coolant: Place a container underneath and partially drain the engine's coolant until its level is below the thermostat housing.
4. Remove Cover: Loosen and remove the bolts securing the thermostat housing cover. Note their positions if they are different lengths.
5. Remove Old Thermostat: Carefully lift off the cover. Remove the old thermostat and the gasket or o-ring.
6. Clean Surfaces: Thoroughly clean the mating surfaces of both the housing and the cover, removing any old gasket material or corrosion.
7. Install New Thermostat: Insert the new thermostat, ensuring it is oriented correctly (the spring side usually faces the engine). It is highly recommended to install a new thermostat gasket (not included) at the same time.
8. Reinstall Cover: Place the cover back on and tighten the bolts evenly in a star pattern to the manufacturer's specified torque. Do not overtighten.
9. Refill & Check: Reattach the hose, refill the cooling system with the appropriate coolant, and reconnect the battery. Run the engine and carefully check for leaks around the housing.

Troubleshooting & FAQ

Q: How do I confirm this thermostat fits my engine?

A: The most reliable method is to match the part number (6FP-12411-00-00) with your engine's service manual. You can also use the compatibility table on this page to check your Yamaha model and year. For further help, consult the Yamaha Serial Number Guide linked above.

Q: What are the common signs of a failing thermostat?

A: A thermostat can fail by sticking open or closed. If it sticks open, your engine may not reach its normal operating temperature, leading to poor performance and fuel economy. If it sticks closed, the engine will overheat, which can cause severe damage.

Q: Some retailers list this part as 62°C, but yours says 60°C. Which is correct?

A: This thermostat is manufactured to the OEM specification of 60°C (140°F). While some aftermarket sources may list a slightly different temperature, our part is designed to open at the correct 60°C for the listed Yamaha engines.

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.