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Sierra 18-1840 Water Dampener Seal for Yamaha Outboard Motors

Manufacturer

Sierra

<p>For nearly six decades, Sierra has established itself as one of the marine industry's most trusted names in aftermarket engine and drive parts. Founded as a specialized marine parts manufacturer, Sierra has grown into a comprehensive supplier of replacement components, instrumentation, and accessories for both recreational and commercial boating applications. Operating from their 300,000-square-foot distribution center in Litchfield, Illinois, Sierra serves boat owners and marine technicians worldwide with an extensive catalog of parts engineered specifically for the harsh saltwater environment.</p><h3>Marine Engine Excellence</h3><p>Sierra's reputation was built on delivering precision-engineered internal engine components and drive system parts that meet or exceed OEM specifications. Their <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> provide critical sealing solutions for inboard and outboard motors, while their <a href="/7570-sierra-engine-complete-assembly-15341">engine complete assemblies</a> offer comprehensive replacement options for major overhauls. Each component undergoes rigorous testing to ensure reliability in demanding marine conditions, from corrosion resistance to temperature cycling performance.</p><h3>Instrumentation and Monitoring Systems</h3><p>Accurate instrumentation is essential for boat operators to monitor engine health and prevent costly breakdowns on the water. Sierra's comprehensive line of <a href="/7570-sierra-gauges-200483">gauges</a> includes everything from fuel pressure and temperature indicators to voltmeters and trim gauges, all designed with marine-grade materials that withstand vibration, moisture, and UV exposure. Their <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauges</a> deliver precise RPM readings critical for optimizing engine performance and fuel efficiency. Supporting these instruments, Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> ensure proper signal conditioning and accurate readings across various sensor types and engine configurations.</p><h3>Expanded Product Portfolio</h3><p>In 2022, Sierra significantly broadened its scope beyond traditional marine engine parts to encompass a wider range of boating accessories and even outdoor power equipment components. This strategic expansion brought established marine brands like Shields and Moeller under the Sierra umbrella, creating a one-stop resource for marine maintenance and replacement parts. The company now offers fuel systems, electrical components, battery charging solutions, and NMEA electronics alongside their traditional engine parts lineup.</p><h3>Quality Backed by Industry-Leading Warranties</h3><p>What sets Sierra apart in the crowded aftermarket marine parts market is their commitment to standing behind every component they manufacture. Their warranty coverage extends beyond simple part replacement—it includes shop labor, haul-out fees, towing charges, and related incidental costs should a warrantied part fail. This comprehensive protection reflects the company's confidence in their manufacturing processes and quality control standards. For boat owners facing repairs far from shore or mechanics working on customer vessels, this peace of mind is invaluable. Whether you're maintaining an outboard motor, rebuilding an inboard engine, or upgrading your boat's instrumentation, Sierra's decades of marine industry experience and commitment to quality make them a reliable choice for keeping your vessel running at peak performance.</p>

Part Number

18-1840
07/14/2036 4:17 PM
Sale Price

$9.01

1 left at this price

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Usually delivered within 2 days

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No Hassle Returns

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra International 18-1840 is a replacement water dampener seal designed for Yamaha outboard motors. This seal is a critical component of the outboard cooling and water pump system, helping to maintain proper water flow and pressure regulation within the engine's lower unit.

Key Features:

  • Direct replacement water dampener seal engineered to meet or exceed original equipment specifications
  • Compatible with Yamaha F2.5 outboards (2015–2020) and Yamaha F4 and F6 outboards (2014–2020)
  • Interchangeable with select Yamaha OEM water dampener seal part numbers
  • Sold as a single seal per package
  • Manufactured by Sierra International, a trusted supplier of marine engine replacement parts

Sierra International has been producing aftermarket marine parts engineered to meet or exceed original manufacturer specifications for decades. The 18-1840 water dampener seal is designed to restore proper function to your Yamaha outboard's cooling system, making it ideal for routine water pump service and maintenance.

They where to big to fit but everything else was good on how fast was delivered n price but just not right thanks

Lets see if you deliver

So far so good

ok

Prices are good, product information is not good enough. I had to search these products elsewhere for any information about them other than the title. If during that search I found the items cheaper someplace else, you would have lost this sale.

I was apprehensiveness at first to make a major purchase with Autoplicity due to their extremely low price and lack of reviews. I decided to take the chance and I am very glad I did. I made my order on a Monday morning at 0900 eastern time and my product arrived on Wednesday at 3pm. The item was exactly as described and the most astonishing part is that my purchase was released from the factory less than 45 days ago. I was expecting a model that had been sitting on a shelf for the last year and needed to be updated. That was not the case. I will definitely order from Autoplicity again in the future.

shipment came very speedy and everything was exactly as expected. All parts were in excellent condition.

great prices and free shipping as well as no tax!

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