PRODUCT DETAILS
Thermostat for Mercury / Mariner Outboard
Fits DFI Optimax 2-Stroke Models – 200HP, 225HP, 250HP, 300HP
This high-quality aftermarket thermostat is designed to maintain proper engine temperature and cooling performance in Mercury Optimax engines.
Will fit the following Mercury/Mariner DFI Optimax models:
• 200 HP DFI – USA models from serial 0G590000 and up
• 225 HP DFI – USA models from serial 0G590000 and up
• 250 HP DFI – USA models from serial 1B426561 and up
• 300 HP DFI – USA models from serial 1E001867 and up
Replaces OEM Part Number:
• Mercury / Mariner 8M0057307
(OEM part number used for reference only. This is a marine-grade aftermarket replacement.)
Why Buy from SSI Marine?
• Marine-grade aftermarket part
• UK-based stock for fast shipping
• Same-day dispatch on orders before 1 PM (Mon–Fri)
• Collection available from our Leigh, Manchester unit
• Trusted supplier with years of marine experience
• VAT invoice available upon request
• Expert help available — message us if you’re unsure about fitment
⚠️ Please confirm compatibility with your engine model and serial number before purchasing. If in doubt, contact us and our team will be happy to help.
SHIPPING & DELIVERY
Delivery:
We offer free shipping on all orders over £150 (excluded outboard engines, trailers)
Standard Shipping - £ 8.50
Orders are typically shipped within 1 business day of receipt of payment. We ship via Royal Mail Tracked 24 delivery service. Delivery times vary depending on the delivery destination.
For engines delivery cost please ask for a quote.
It is the buyer's responsibility to ensure that the correct shipping address is supplied.
All item(s) will be despatched to the registered address.
Tracking your order:
Once your order has been shipped, you will receive a tracking number via email. You can track your order online using the tracking number provided.
Returns:
We accept returns of unused and undamaged items within 30 days of purchase.
To return an item please contact us for a return authorisation number. Return shipping costs are the responsibility of the customer.
Refunds:
Refunds will be issued for the purchase price of the item, less shipping costs. Refunds will be issued in the same form of payment as the initial purchase.
YOU MIGHT ALSO LIKE
OFFICIAL PARTNERS OF
