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Sierra 18-1825 Marine Water Pump Grommet for Johnson/Evinrude 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

18-1825
08/04/2036 11:21 PM
Sale Price

$15.49

1 left at this price

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-1825 is a precision-fit marine water pump grommet designed as a direct replacement component for Johnson/Evinrude outboard motors. This grommet is a critical sealing and cushioning element within the outboard cooling system, forming a secure, vibration-dampening connection between water pump components to maintain proper flow and prevent leaks.

The Sierra 18-1825 corresponds to OEM part number 340811 and is a standard service component found in water pump kits for Johnson/Evinrude 4 HP (1986–1992), 5 HP (1980–1983, 1996–2001), 6 HP (1984–2001, 2003–2005), and 8 HP (1980–2001, 2003–2005) outboard motors, as well as 25/35 HP (1996–2001) applications.

Key Features:

  • Direct OEM replacement grommet — replaces Johnson/Evinrude/OMC OEM part 340811
  • Meets or exceeds original equipment quality and performance standards
  • Constructed from durable, marine-grade materials engineered to withstand harsh saltwater and freshwater environments
  • Provides a secure seal and reduces vibration within the water pump assembly
  • Sold individually (qty: 1)
  • Component of Sierra water pump kits 18-3491 and 18-4529

Sierra International is the marine industry's leading supplier of aftermarket engine parts, offering products engineered to OEM specifications for long-lasting reliability on the water.

It was easy to find what we needed and to order it.

hard to find... found it here

I had to cross reference the manufacturer website to find out which was the inner and outer tie rods. A better description could have made that easier. Thanks guys!

quick and easy to order

so far so good other than the item description shows JEEP..which is confusing

so far, so good. let's see if it shows up in the timeframe estimated.

same part Firestone quoted me190 for....this was a huge savings.

Best price on FX400, smooth easy website.

Lowest price! Fast shipping!!

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