Thermostat for Yamaha F225F, F250D & F300B Four-Stroke Outboards – 52°C
Thermostat for Yamaha F225F, F250D & F300B Four-Stroke Outboards – 52°C is backordered and will ship as soon as it is back in stock.
Worry-free returns
Worry-free returns
Shop with confidence. If you’re not completely satisfied, eligible items may be returned within the return window, provided they are unused and in original packaging.
If the return is due to our error or a defective item, we’ll make it right.
Please contact us before returning any item.
Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
International delivery times may vary due to customs processing.
Tracking information will be provided once your order ships.
Thermostat for Yamaha F225F, F250D & F300B Four-Stroke Outboard...
Thermostat for Yamaha F225F, F250D & F300B Four-Stroke Outboards – 52°C is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket thermostat is specified for Yamaha F225F, F250D, and F300B four-stroke outboard engines. It is designed to regulate engine temperature at the listed 52°C operating specification and provides a replacement option for the applicable original thermostat.
The listed manufacturer references are Yamaha 6CE-12411-00 and 6CE-12411-10-00. The aftermarket reference associated with this thermostat is 18-3524.
- 52°C temperature specification.
- Replacement thermostat for the engine cooling system.
- For Yamaha F225F, F250D, and F300B four-stroke outboards.
- Verify the complete engine model and existing thermostat reference before ordering.
Part Number Matrix
Use the following references to compare your original component with this replacement thermostat.
| Brand or Source | Part Number | Reference Type |
|---|---|---|
| Yamaha | 6CE-12411-00 | Manufacturer reference |
| Yamaha | 6CE-12411-10-00 | Manufacturer reference |
| Aftermarket | 18-3524 | Aftermarket reference |
Engine & Model Compatibility
This listing is based on the company fitment record for the following Yamaha four-stroke outboard models. Model, year, shaft length, and serial-number coverage are not specified in that record, so confirm those details against your engine documentation before installation.
| Brand | Model | Rated HP | Stroke | Year or Serial Range | Manufacturer References |
|---|---|---|---|---|---|
| Yamaha | F225F | 225 | 4-Stroke | Not specified | 6CE-12411-00; 6CE-12411-10-00 |
| Yamaha | F250D | 250 | 4-Stroke | Not specified | 6CE-12411-00; 6CE-12411-10-00 |
| Yamaha | F300B | 300 | 4-Stroke | Not specified | 6CE-12411-00; 6CE-12411-10-00 |
Technical Specs
- Product Type
- Thermostat
- Application
- Yamaha four-stroke outboard cooling system
- Operating Temperature
- 52°C
- Applicable Models
- Yamaha F225F, F250D, and F300B
- Manufacturer References
- 6CE-12411-00 and 6CE-12411-10-00
- Aftermarket Reference
- 18-3524
What’s in the Box
- 1 x Thermostat
This listing is for the thermostat only. A housing gasket or other installation hardware is not specified as included; reuse or replacement of those items should be determined during service.
Installation Notes
- Confirm the engine model and the reference on the thermostat being replaced before beginning work.
- Allow the engine to cool completely and follow the safety procedures in the applicable Yamaha service manual.
- Remove the thermostat housing carefully and note the orientation of the original thermostat.
- Remove the old thermostat and clean the housing and mating surfaces without damaging them.
- Install the replacement thermostat in the same orientation as the original component.
- Inspect the housing seal or gasket and replace it if required for a proper seal.
- Reinstall the housing and tighten the fasteners to the manufacturer’s specified torque.
- Run the engine according to the service procedure and check for leaks or abnormal temperature behavior.
Troubleshooting & FAQ
What does this thermostat do?
The thermostat controls coolant flow through the engine cooling system so the engine can operate near its specified temperature.
Which Yamaha engines are listed for this thermostat?
The company fitment record lists Yamaha F225F, F250D, and F300B four-stroke outboards. Confirm the complete model designation and the reference on your existing thermostat before ordering.
What temperature is this thermostat specified for?
The listed operating-temperature specification is 52°C.
Which manufacturer references should I compare?
Compare your original thermostat with Yamaha references 6CE-12411-00 and 6CE-12411-10-00. The associated aftermarket reference is 18-3524.
Is a gasket included?
No gasket is specified as included. This listing is for one thermostat, so inspect the existing seal and replace it if required by the service procedure.
Can I install this thermostat myself?
Installation should be performed only by someone familiar with outboard cooling-system service. Always follow the service manual for the exact engine model, fastener torque, sealing procedure, and post-installation checks.
Is this an OEM component?
This is an aftermarket replacement thermostat. Yamaha references are provided for identification and fitment comparison only.
How should I confirm fitment?
Check the full engine model, year or serial information, the original thermostat reference, and the physical replacement before installation. Do not rely on horsepower alone to determine fitment.
Safety & Important Information
- Allow the engine to cool completely before servicing the thermostat.
- Verify the full engine model and manufacturer reference before ordering.
- Model, year, shaft, and serial-number coverage is not specified beyond the listed model fitment; confirm those details using your engine documentation.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended when the applicable service procedure or torque specifications are not available.
About Sea Sierra
- Marine Replacement Parts — We supply replacement components for marine service and repair applications.
- Fitment-Focused Information — Product references and model details are provided to help you compare the replacement with your original part.
- Service-Ready Support — Always use the applicable engine service documentation for installation and maintenance procedures.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
