Mercury Quicksilver — Thermostat Gasket — 8M0204714
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Mercury Quicksilver Thermostat Gasket 8M0204714
Mercury Quicksilver 8M0204714 is a genuine OEM thermostat gasket used to seal the thermostat connection in the engine cooling system on a wide range of Mercury and Mariner outboards. It is the current replacement for earlier Mercury gasket numbers 62386 and 62386001.
Compatible Applications
- Mercury and Mariner 135 HP outboards
- Mercury and Mariner 140 Jet 2.5L applications
- Mercury and Mariner 150 HP outboards
- Mercury and Mariner 175 HP outboards
- Mercury and Mariner 200 HP outboards
- Mercury V-200 EFI 2.5L applications
- Mercury XR6 applications
- Mercury Magnum III applications
- Mercury and Mariner 150, 175, and 200 DFI 2.5L applications
- Mercury 200 DFI Jet Drive applications
- Additional thermostat-equipped outboards whose diagram specifies 62386, 62386001, or 8M0204714
Serial-number fitment: Mercury used the earlier gasket numbers across different serial ranges before consolidating them under 8M0204714. Confirm the engine serial number and thermostat diagram before ordering rather than relying on horsepower alone.
Part Details
- Current part number: 8M0204714
- Catalog-form number: 27-8M0204714
- Brand: Mercury Quicksilver
- Product type: Thermostat gasket
- System: Engine cooling and thermostat
- Supersedes: 62386 and 62386001
- Approximate weight: 0.01 lb or 4.5 g
- Condition: New
Key Features
- Genuine OEM thermostat gasket
- Seals the thermostat connection against cooling-water leakage
- Used individually, with quantity confirmed by the engine diagram
- Many Mercury 2.5L V6 applications use two thermostat assemblies and may require two gaskets per engine
When to Replace This Gasket
Replace the gasket whenever the thermostat or thermostat cover is removed, cooling water is leaking at the thermostat connection, or the existing gasket is compressed, torn, hardened, or damaged. A previously compressed gasket should not be reused after the joint has been opened.
Installation Notes
Clean the thermostat and mating surfaces without damaging them. Confirm that the thermostat, cover, gasket, and related components match the serial-number-specific diagram. On V6 engines with a thermostat on each cylinder bank, inspect both assemblies during the same service and replace every gasket disturbed during disassembly. Follow the applicable service procedure for thermostat orientation and fastener specifications.
Technical FAQ
How many gaskets are required?
Quantity varies by engine. Many Mercury 2.5L V6 applications use two thermostats and may require two gaskets.
What earlier numbers does this gasket replace?
8M0204714 supersedes Mercury 62386 and 62386001.
Can fitment be confirmed by horsepower alone?
No. Match the engine serial number and thermostat diagram because the gasket spans multiple engine generations and cooling-system configurations.
Parts Desk Insights
Best use case: Installing a fresh thermostat seal whenever the thermostat cover is opened for inspection, cooling-system service, or related cylinder-head work.
Most common mistake: Ordering one gasket for a V6 application that uses a thermostat on each cylinder bank. Check the diagram quantity before starting service.
Fitment guidance: Use the original part number or serial-number-specific cooling-system diagram as the primary fitment check rather than gasket appearance or horsepower alone.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.