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Sierra 18-3804 Marine Cylinder Head Gasket for Mercury/Mariner & Yamaha Outboards

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3804
15 reviews
Sale Price

$39.24

In Stock (6)

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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 18-3804 is a direct-fit replacement cylinder head gasket engineered for Japanese-built Mercury/Mariner 30A outboard motors (serial number code 689) and compatible Yamaha 25HP and 30HP two-stroke outboard engines. Designed as a stock replacement, this gasket meets or exceeds original equipment manufacturer (OEM) specifications for a reliable, leak-free seal between the cylinder head and engine block.

Key Features:

  • Manufactured to meet or exceed OEM quality and performance standards
  • Engineered to withstand the demanding conditions of the marine environment
  • Exact-fit design minimizes labor time during installation
  • Covered under Sierra's industry-leading limited lifetime warranty
  • Sold individually

OEM Cross-Reference Numbers:

  • Mercury Marine: 27-19138, 27-19138M, 27-84733M
  • Yamaha: 689-W0001-A1-00, 689-11181-02-00, 689-11181-A1-00
  • GLM: 33880
  • Mallory: 9-63960

Sierra International is a recognized leader in aftermarket marine engine parts, supplying OEM engine manufacturers and boat builders with high-quality components. The 18-3804 head gasket is an ideal choice for technicians and boaters performing cylinder head service or powerhead rebuilds on applicable Mercury/Mariner and Yamaha outboard motors.

Outstanding transaction. I was amazed my filters were delivered in less than 48 hours from ordering. Well done!

The parts I received were of high quality and met my expectations.

na

I am very pleased with the product and delivery time.

Great job fast

I like how autoplicty puts listing on ebay so you have more options for cheaper prices.

One of the top 10 places online to find the best deals on performance parts, either for street or strip. In the last two weeks I found more better deals at Autoplicity then at any other online performance parts store.. Gone_10_in_Sec..

Very easy and quick ordering process, so far so good. Completely satisfied with the product and the speed of shipment. Would gladly do business again with Autoplicity.

Easy order process, Good price

Super easy and Quick! Called Tech. Support to confirm my part selection/fit. Really fast delivery for coming from the east coast. BUT, Part was not as pictured. I actually purchased because of the BOSAL brand and the picture was identical to the one I nee

Easy peasy lemon squeezie

Cheapest price I found! And super speedy deliver! Impressed!

Quick and Easy, Ordered on 4/23/15 and received on 4/28/15. Just what I need, fits my Undercover Tonneau cover perfectly. Great place to buy. Will buy from again. Great Job!! Thanks

Easy

Best price on internet. Local dealer wanted 325 dollars more for exact item. Great place to do business.

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