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Sierra 18-3861 Cylinder Head Gasket for Mercury/Mariner V6 Outboard Motors

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3861
12 reviews
Sale Price

$43.30

In Stock (10+)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3861 is a replacement cylinder head gasket engineered for Mercury and Mariner V6 2.0L two-stroke outboard motors. This head gasket directly replaces Mercury Marine OEM part numbers 27-18785-1, 27-18785T, and 27-187853, as well as GLM 35850 and Mallory 9-63851, making it a reliable aftermarket solution for marine engine rebuilds and cylinder head service.

Key Features:

  • Direct OEM replacement head gasket for Mercury and Mariner V6 outboard engines
  • Designed for 2.0L engines with dowel pin cylinder heads and 79.4 mm pistons
  • Engineered to meet or exceed original equipment manufacturer specifications
  • Built to withstand the demands of high-horsepower marine engine environments
  • Restores proper cylinder sealing and compression to OEM performance levels

OEM Cross-Reference:

  • Mercury Marine: 27-18785-1, 27-18785T, 27-187853
  • GLM: 35850
  • Mallory: 9-63851

Sierra has been a trusted manufacturer of aftermarket marine engine parts for decades, supplying OEM engine manufacturers and boat builders worldwide. The 18-3861 head gasket is designed to fit right the first time, ensuring a proper seal and reliable performance when servicing Mercury 135, 150, and XR4 V6 outboard engines.

2nd time ordering best deal found here

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I ordered the correct Ranch Hand Bumper part number for my 2006 GMC Sierra 2500HD, but your description says it's for a 1500HD. I hope it is for my truck. It's a great deal if correct!

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Great site - Great experiance

By far the fastest shipping I've ever had online! Great business to work with and had the cheapest price I could find!

Ordered a cover for my Jeep. Price was extemely fair and shipped the next morning. Plus I like the variety of products that they have.

Great product, price and service and FREE delivery. Got my order in only 2 days.

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