Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
Welcome Offer : Use Code WELCOME5 for 5% OFF your first order!
Free Shipping Across USA
- No EU import duties. - Ships within 3-5 business days. (USA) - Ships with 8-12 business days. (International)
⚠️ California Proposition 65 Warning : Some products sold on this website may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.
For more information, visit www.P65Warnings.ca.gov.
Sierra'S 18-3638 Thermostat Is Designed For Use With Mercury/Mariner 2.5 Hp To 3.5 Hp (S/N 0R131842 & Up) And 4 Hp To 6 Hp (S/N 0R411838 & Up) Outboard Engines. Includes One Thermostat Per Package. It Is Interchangeable With Mercury Marine 804540. Each Sierra Product Meets Or Exceeds The Original Equipment Part It Replaces. Fit Specific, Check Part Numbers To Ensure Proper Fit.
Yes, we offer free standard shipping on all orders within the United States.
When will I receive my item?
Domestic orders typically arrive within 3-5 business days. Delivery times are estimated and may vary depending on your location, weather conditions, or other unforeseen factors.
Can I change or return my item?
We hope you love your purchase, but if you need to make a change or return your item, we’ve got you covered! You can initiate a return or exchange within 30 days of receiving your order. Please ensure the product is in its original condition and packaging. For more information on our return policy, please visit our Returns & Exchanges page.
Frequently Asked Questions
Q: What outboard engines are compatible with the Sierra 18-3638 Thermostat?A: The Sierra 18-3638 Thermostat is designed for use with Mercury/Mariner outboard engines ranging from 2.5 HP to 3.5 HP (serial numbers 0R131842 and up) and 4 HP to 6 HP (serial numbers 0R411838 and up).
Q: Is the Sierra 18-3638 Thermostat interchangeable with other brands?A: Yes, the Sierra 18-3638 Thermostat is interchangeable with Mercury Marine part number 804540, making it a versatile replacement option.
Q: How many thermostats are included in the package?A: Each package of the Sierra 18-3638 Thermostat includes one thermostat.
Q: Does the Sierra 18-3638 Thermostat meet OEM standards?A: Yes, every Sierra product, including the 18-3638 Thermostat, meets or exceeds the original equipment manufacturer (OEM) specifications for the part it replaces.
Q: How can I ensure proper fit for my outboard engine?A: To ensure a proper fit, it is essential to check the part numbers of your existing thermostat and compare them with the Sierra 18-3638 Thermostat before purchasing.
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