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Sierra 18-2534 Spaghetti Seal 40" Lower Unit Gearcase Seal

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

18-2534
06/04/2036 8:59 AM
Sale Price

$13.09

3 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 18-2534 is a 40-inch spaghetti seal designed for outboard motor lower unit gearcase applications. This critical sealing component helps prevent gear oil leakage and keeps water from intruding into the gearcase, protecting the internal components of Johnson, Evinrude, and OMC outboard motors.

Key Features:

  • 40-inch length universal spaghetti seal
  • Manufactured with OEM-equivalent materials for reliable sealing performance
  • Replaces OEM part numbers: OMC 309044, Chrysler/Force F184122-1, and Mallory 9-78007
  • Designed for split-case lower unit assemblies
  • Fits in gearcase housing grooves to create a water-tight seal between upper and lower unit halves

This replacement seal meets or exceeds original equipment specifications and is a critical component during lower unit rebuilds and gearcase maintenance. Proper installation with marine-grade sealant ensures optimal protection against oil loss and water contamination in the gearcase.

Great

Fast ordering process

easy to use site, great price, wide choice of payment types

Fast and hopefully easy

Excellent selection, great prices, and fast shipping. I am very satisfied.

Good contents of what I was looking for. Pretty quick.

Fast and easy

great ! except i signed up for 20% discount and wasn't applied. that sucks.

I will be back with you guys

Very good prices and incredibly fast shipping. Shipping costs were a bit high but I would definitely use them again!

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