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Thermostat Gasket – Fits Mercury/Mercruiser Marine Engines (Replaces 27-62386001)

Sale price $8.99 Regular price $14.00
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You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

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Product Details

This Thermostat Gasket – Fits Mercury/Mercruiser Marine Engines (Replaces 27-62386001) ensures a reliable seal for the thermostat housing in a wide range of Mercury and Mariner outboard engines. It is designed for compatibility with various models from 6 to 200 HP, including 3-cylinder and V6 configurations, providing a direct-fit replacement for the original part.

This component provides a direct replacement for Mercury/Quicksilver part numbers 27-62386001 and 8M0204714, as well as Mercruiser part 27-62386001.

  • Installation Method: Direct OEM-style replacement
  • Primary Application: Seals the thermostat housing to prevent coolant leaks
  • Package Contents: Includes one thermostat gasket

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number Superseded By
Mercury/Quicksilver 27-62386001 8M0204714
Mercruiser 27-62386001

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury/Mariner Outboard engines, this gasket fits a variety of models. Please verify your specific engine in the list.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Mercury 6 6 27-62386001 Superseded by 8M0204714
Mercury 8 8 27-62386001 Superseded by 8M0204714
Mercury 9.9 9.9 27-62386001 Superseded by 8M0204714
Mercury 10 (MARATHON, SEA PRO, VIKING) 10 27-62386001 Superseded by 8M0204714
Mercury 15 (incl. MARATHON, SEA PRO, VIKING) 15 27-62386001 Superseded by 8M0204714
Mercury 20 (2 CYL.) 20 27-62386001 Superseded by 8M0204714
Mercury 20 JET 20 27-62386001 Superseded by 8M0204714
Mercury 25 (2 CYL.) 25 27-62386001 Superseded by 8M0204714
Mercury 30 (2 CYL.) 30 27-62386001 Superseded by 8M0204714
Mercury 40 (2 CYL.) 40 27-62386001 Superseded by 8M0204714
Mercury 40 JET 40 27-62386001 Superseded by 8M0204714
Mercury 55 (3 CYL.) 55 27-62386001 Superseded by 8M0204714
Mercury 60 (3 CYL.) 60 27-62386001 Superseded by 8M0204714
Mercury 65 JET (3 CYL.) 65 27-62386001 Superseded by 8M0204714
Mercury 75 (3 CYL.) 75 27-62386001 Superseded by 8M0204714
Mercury 75 DFI (3 CYL.)(1.5L) 75 27-62386001 Superseded by 8M0204714
Mercury 80 JET 80 27-62386001 Superseded by 8M0204714
Mercury 80 Jet (3 CYL.)(1.5L) 80 27-62386001 Superseded by 8M0204714
Mercury 90 (3 CYL.) 90 27-62386001 Superseded by 8M0204714
Mercury 90 DFI (3 CYL.)(1.5L) 90 27-62386001 Superseded by 8M0204714
Mercury 110 Jet (2.5L) 110 27-62386001 Superseded by 8M0204714
Mercury 115 (4 CYL.) 115 27-62386001 Superseded by 8M0204714
Mercury 115 DFI (3 CYL.)(1.5L) 115 27-62386001 Superseded by 8M0204714
Mercury 115 Pro XS (3 CYL.)(1.5L) 115 27-62386001 Superseded by 8M0204714
Mercury 125 (4 CYL.) 125 27-62386001 Superseded by 8M0204714
Mercury 125 DFI (3 CYL.)(1.5L) 125 27-62386001 Superseded by 8M0204714
Mercury 140 JET 140 27-62386001 Superseded by 8M0204714
Mercury 150 Pro XS (2.5L) 150 27-62386001 Superseded by 8M0204714
Mercury 175 PROXS (2.5L) 175 27-62386001 Superseded by 8M0204714
Mercury MAGNUM III 27-62386001 Superseded by 8M0204714
Mercury V-135 135 27-62386001 Superseded by 8M0204714
Mercury V-135 DFI (2.5L) 135 27-62386001 Superseded by 8M0204714
Mercury V-140 (INTERNATIONAL) 140 27-62386001 Superseded by 8M0204714
Mercury V-150 150 27-62386001 Superseded by 8M0204714
Mercury V-150 DFI (2.5L) 150 27-62386001 Superseded by 8M0204714
Mercury V-150 EFI (2.5L) 150 27-62386001 Superseded by 8M0204714
Mercury V-175 DFI (2.5L) 175 27-62386001 Superseded by 8M0204714
Mercury V-200 200 27-62386001 Superseded by 8M0204714
Mercury V-200 EFI (2.5L) 200 27-62386001 Superseded by 8M0204714
Mercury XR-6 27-62386001 Superseded by 8M0204714
Mercury 2.5L (EFI)/(EFI-OFFSHORE) 27-62386001 Superseded by 8M0204714
Mercury 2.5XS 2.5L DFI 27-62386001 Superseded by 8M0204714
Mercury 200XS DFI (2.5L) 200 27-62386001 Superseded by 8M0204714
Mercury 200XS DFI (2.5L) ROS 200 27-62386001 Superseded by 8M0204714
Mercury 200XS SST 200 27-62386001 Superseded by 8M0204714
Mercury 200 DFI JET DRIVE (POWERHEAD) 200 27-62386001 Superseded by 8M0204714
Mercury 200 DFI M2 JET DRIVE (PUMP) 200 27-62386001 Superseded by 8M0204714

Technical Specs

Product Type
Thermostat Gasket
Installation
Direct OEM replacement
Dimensions
1.13 × 5.13 × 4.0 inches (approx. 28.7 × 130.3 × 101.6 mm)
Weight
0.02 kg (0.044 lbs)
Country of Origin
Venezuela
Manufacturer
Mercury Marine/Quicksilver
OEM Part Number
27-62386001 (Superseded by 8M0204714)
Application
Thermostat housing seal

What’s in the Box

  • 1 x Thermostat Gasket (27-62386001/8M0204714)

Installation Notes

  1. Ensure the engine is off and cool. Disconnect the negative battery terminal for safety.
  2. Drain the engine coolant to a level below the thermostat housing to prevent spills.
  3. Locate the thermostat housing on the engine. Carefully remove the bolts or fasteners securing it.
  4. Gently lift the housing away. You may need to lightly tap it to break the old seal.
  5. Remove the old thermostat gasket. Thoroughly clean both the engine and housing mating surfaces, ensuring they are free of old gasket material, sealant, and debris.
  6. Position the new gasket correctly on the engine block's thermostat recess.
  7. Reinstall the thermostat housing, ensuring it is properly aligned.
  8. Tighten the housing bolts in a crisscross pattern to the manufacturer's recommended torque specifications to ensure an even seal. Do not overtighten.
  9. Refill the cooling system with the appropriate coolant.
  10. Reconnect the battery terminal, start the engine, and let it warm up. Carefully inspect the thermostat housing area for any signs of leaks.

Troubleshooting & FAQ

How do I confirm this gasket will fit my engine?

This gasket fits a wide range of Mercury and Mariner outboards (6–200 HP). Please review the detailed compatibility table and cross-reference your engine model and original part number. If your part number is 27-62386001 or the superseded 8M0204714, this part is a correct fit.

What are the signs of a failing thermostat gasket?

Common symptoms include visible coolant leaks or dried coolant residue around the thermostat housing, engine overheating alarms, or erratic temperature gauge readings. A leak can lead to low coolant levels and engine damage if not addressed.

Do I need to use sealant when installing this gasket?

Typically, this type of gasket is designed for a dry installation. However, always refer to your engine's official service manual. Some applications or scored surfaces might require a thin layer of a specific marine-grade sealant.

What is the purpose of the thermostat gasket?

The thermostat gasket creates a fluid-tight seal between the thermostat housing and the engine block. This prevents coolant from leaking out while ensuring the thermostat can accurately regulate the engine's operating temperature for optimal performance and fuel efficiency.

How often should I replace my thermostat gasket?

It is best practice to replace the thermostat gasket anytime the thermostat itself is replaced or when the housing is removed for any cooling system service. There is no fixed interval, but it's a low-cost preventative part to replace during related maintenance.

Is this a direct replacement for Mercury/Quicksilver part 27-62386001?

Yes, this is a direct, aftermarket replacement for OEM part 27-62386001 and its functional replacement, 8M0204714. It is designed to meet or exceed original specifications for fit and function.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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