Gasket – Fits Mercury Marine 70–125 HP (Replaces Mercury Marine 27-43008/27-430082/27-430083/27-430085/27-430086)

Product Details

This aftermarket Gasket – Fits Mercury Marine 70–125 HP is engineered for a precise fit on a wide range of Mercury Marine engines, including 70 to 125 HP 2-stroke, 4-stroke, and DFI models from approximately 1995 to current production years. It ensures a reliable seal for the exhaust plate components.

It serves as a direct cross-reference for Mercury Marine part numbers 27-43008, 27-430082, 27-430083, 27-430085, and 27-430086, along with Sierra part 18-0341.

• Engineered to meet or exceed original factory equipment specifications.
• Provides a durable, heat-resistant seal for marine exhaust systems.
• Designed for compatibility with both Mercury Marine and Force outboard models.

Part Number Matrix

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

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury Marine Engines: This gasket fits a wide variety of 3-cylinder and 4-cylinder models from the mid-1990s onward, including DFI and Pro XS series. Please verify your engine's serial number falls within the specified ranges.

For Force Engines: This part is compatible with specific 75 HP, 90 HP, and 120 HP Force outboard models from 1995 to 1999. Check your model year and serial number range to ensure a correct match.

Technical Specs

Product Type

Gasket

Design

Built to meet OEM factory specifications

Dimensions

Length: 13.0 in (330.2 mm) | Width: 10.0 in (254 mm) | Height: 0.13 in (3.3 mm)

Weight

0.058 kg (0.13 lbs)

What’s in the Box

• 1 x Gasket (Replaces 27-430086)

Installation Notes

1. Ensure the engine is off and cool, and disconnect the battery for safety.
2. Drain coolant or other relevant fluids to prevent spills during disassembly.
3. Carefully remove any interfering components to access the old exhaust plate gasket.
4. Thoroughly clean both mating surfaces to remove all old gasket material, sealant, and debris. A clean, smooth surface is critical for a proper seal.
5. Position the new gasket onto the clean surface, ensuring all bolt holes are correctly aligned.
6. Reassemble the exhaust plate and other components. Tighten all fasteners in a star or crisscross pattern to the manufacturer-specified torque values.
7. Refill any drained fluids, reconnect the battery, and start the engine. Check carefully for any exhaust or fluid leaks around the new gasket.

Troubleshooting & FAQ

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.