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

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

18-1825
09/12/2036 6:55 AM
Sale Price

$15.49

1 left at this price

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Usually delivered within 2 days

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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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