18-0918 Plate to Exhaust Manifold Gasket for 2-stroke 50hp Mercury/Mariner engines - 4Boats

Sierra 18-0918 Exhaust Manifold Gasket Mercury Mariner 50HP 2-Stroke

18-0918 L4

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Regular price£29.99
/
Tax included.

Sierra 18-0918 Exhaust Gasket

Mercury / Mariner 50HP two-stroke applications

The Sierra 18-0918 is a plate-to-exhaust-manifold gasket for compatible Mercury and Mariner 50HP two-stroke outboards. It provides the heat-resistant sealing surface required when the exhaust plate or manifold is removed.

FITMENT CHECK: Match Sierra 18-0918 in the serial-number-specific parts diagram; 50HP alone does not guarantee the same exhaust assembly.

Key Features

  • ✔ Genuine Sierra-branded aftermarket gasket
  • ✔ Plate-to-exhaust-manifold application
  • ✔ Heat-resistant gasket material
  • ✔ For selected 50HP two-stroke outboards
  • ✔ One gasket supplied

Technical Specs

Brand Sierra
Part number 18-0918
Part type Exhaust manifold / plate gasket
Typical application Mercury / Mariner 50HP two-stroke
Quantity 1 gasket
4Boats SKU 18-0918 L4

Compatibility / Fitment Guide

Listed for selected Mercury and Mariner 50HP (37kW) two-stroke outboards using the corresponding exhaust plate and manifold. Confirm the gasket outline, original reference and engine serial number before ordering.

Part Number Cross Reference

Sierra 18-0918
4Boats SKU 18-0918 L4

This is a genuine Sierra aftermarket gasket, not a Mercury or Mariner-branded part.

Questions & Answers

Is this a genuine Mercury gasket?

No. It is a genuine Sierra replacement.

Does it fit every Mercury 50HP?

No. Confirm the exhaust assembly and serial number.

How many are included?

One gasket is supplied.

Can the old gasket be reused?

A new gasket should be installed whenever the joint is dismantled.

Note: Clean the mating surfaces carefully and follow the engine manual for sealant, bolt sequence and torque.

For the products under £150 the shipping is £6.99.

Free delivery for most items over £150.

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