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Sierra 18-3921 Marine Piston Ring Set for Mercury Outboard Engines

Manufacturer

Picture for manufacturer Sierra

Part Number

118-3921
8 reviews
Sale Price

$32.11

1 left at this price

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Usually delivered within 2 days

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3921 is a standard bore piston ring set designed specifically for Mercury Marine outboard engines. This high-quality replacement part is engineered to meet or exceed OEM specifications, ensuring reliable performance in harsh marine environments.

Key Specifications:

  • Bore Size: 3.125 inches (standard)
  • Includes two piston rings per set
  • Designed for Mercury 2.0 Liter V6 engines
  • Premium aftermarket replacement quality

OEM Cross-References:

  • Mercury Marine 39-93481A12
  • GLM 14240
  • Mallory 9-54233
  • Wiseco 3125KD

Sierra piston rings are manufactured to provide proper cylinder sealing, efficient heat transfer from the piston to the cylinder wall, and optimal compression retention. These rings help maintain engine performance and longevity by preventing combustion gas leakage while ensuring adequate clearance for thermal expansion.

Good experience

Parts delivered as promised. THMotorsports.com is Bookmarked in my explorer

Product came very quickly, it's just what I was looking for.

The Livewell Pump arrived and worked great! Thank you.

Everything is very convenient and simple.5+

Easy ordering. Great seller.

This was very quick and pleasant to work with and I will use them again if needed.

All good!

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