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Sierra 18-2004 Marine Oil Seal for Mercury/Mariner Outboard Motors

Manufacturer

Picture for manufacturer Sierra

Part Number

18-2004
9 reviews
Sale Price

$17.22

1 left at this price

delivery box

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 18-2004 is a precision-engineered marine oil seal designed for use on Mercury and Mariner outboard motors. Built to meet or exceed the original equipment manufacturer (OEM) standards, this replacement seal helps maintain a leak-free engine and protects critical internal components from contamination and wear.

Oil seals play a vital role in outboard motor reliability by preventing oil and grease from escaping while blocking dirt, water, and other foreign matter from entering shafts and bearings. The Sierra 18-2004 delivers OEM-equivalent performance at an aftermarket value, making it a trusted choice for routine maintenance and lower unit service.

Key Features:

  • Designed to meet or exceed OEM specifications for Mercury/Mariner outboard motors
  • Protects shafts and bearings from oil leakage and contaminant ingress
  • Component of Sierra's Mercury Marine lower unit seal system
  • Backed by the SeaStar Solutions industry-leading warranty
  • Reliable fit for routine maintenance and lower unit rebuilds

Sierra marine engine parts are produced by SeaStar Solutions, the market leader in aftermarket marine engine components, covering virtually every major engine brand on the water today.

everything was very user friendly.

I just placed an online order, the site seems easy to use.

Very easy to find difficult parts to find

Easy an fast

quick, as long as what is ordered is what i get.

Pretty easy so far... site is slow though.

Extremely satisfied with my transaction with Autoplicity. Item was shipped out almost immediately after I paid. Customer support responded very quickly and answered all of my questions in a very professional manner. Will definitely be shopping here in the future.

Great prices I found exactly what I needed without paying that much, I found the product lower than thee competitors. They send me emails and keep me posted on my product and give me a tracking number so I can locate where its at. Im excited to recieve my mishimoto oil catch can.

5 STAR MERCHANT! Recommend to everybody. Extremely quick, relieable, honest, and accurate. Item was delivered 2 days sooner than they told me in perfect condition. Additionally, they were the least expensive for the item. I do not know how they do it but they did it.

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