My Account
Shopping Cart

Sierra 118-7100-9 Marine O-Ring 5-Pack Replacement 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

118-7100-9
06/03/2036 4:57 AM
Sale Price

$8.95

1 left at this price

delivery box

Usually delivered within 2 days

Authorize Seller Badge
No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 118-7100-9 Marine O-Ring is a precision-engineered replacement seal designed for marine engine applications. This reliable component provides leak-proof sealing for lower units, gearcase assemblies, and shift rod applications across multiple marine engine brands.

Key Specifications:

  • Inner Diameter: 0.245" (6.2mm)
  • Width: 0.155" (3.9mm)
  • Package Quantity: 5 O-rings per pack
  • Meets or exceeds OEM specifications

OEM Cross-References:

  • Chrysler/Force/US Marine: 25-85594
  • Johnson/Evinrude Outboard: 301877
  • Mercury Marine: 25-85594
  • OMC Stern Drive: 301877
  • GLM: 45230
  • Mallory: 9-76509

Sierra Marine parts are manufactured to meet original equipment quality standards, ensuring proper fit and durability. These O-rings are commonly used for gearcase sealing and shift rod applications, particularly effective at preventing lower unit leaks in OMC and Johnson/Evinrude outboard motors. The convenient 5-pack ensures you have spare seals on hand for maintenance and repairs.

Very easy!

A+

Found product at a lower price than a couple of other sites convenient fast shipping with quality of followup of product ordered thanks

Good prices. So far so good

Thank you, perfect

Received the order in a timely manner and worked perfectly

This is my first order from you. So, we will see how it works out.

Hello...I&#039;m a new customer and I&#039;m very excited to receive the parts I ordered and it gets here on time. Thank you

Quick easy and affordable love the website found what I was looking for and what I wanted

Share icon
Return Policy
Returns are easy at Boatplicity

Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy