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Sierra 18-3902 Marine Piston Ring Set for Mercury/Mariner Outboard Motors

Manufacturer

Picture for manufacturer Sierra

Part Number

118-3902
6 reviews
Sale Price

$33.09

1 left at this price

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3902 is a high-quality marine piston ring set engineered for Mercury and Mariner outboard motors. Designed to meet or exceed OEM specifications, this replacement piston ring set delivers reliable performance and durability in demanding marine environments.

Key Features:

  • For 3-ring pistons with 2.875-inch standard bore size
  • Compatible with Mercury/Mariner outboard motors ranging from 35-150 HP
  • Precision-manufactured to meet OEM specifications
  • Direct replacement for Mercury Marine part numbers 39-78816A12 and 39-45155A12
  • Also interchangeable with Mallory 9-54217

Sierra marine engine components are built to provide dependable performance and long service life. Each ring set is manufactured to exact tolerances to ensure proper compression and optimal engine operation. When it's time to rebuild your Mercury or Mariner outboard, trust Sierra for quality replacement parts that deliver professional results.

Quality of products (Marine grade cabinet hardware & hooks) was excellent and as expected. Delivery was quick. Everything came in two shipments. The first arrived faster then indicated, the second exactly as indicated. Smooth experience.

Give better confirmation emails

5 Star

Easy order

Very smooth

It was fast and easy!

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