My Account
Shopping Cart

Sierra 18-1165 Tapered Roller Bearing for MerCruiser Stern Drives

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

18-1165
08/04/2036 2:50 PM
Sale Price

$40.99

In Stock (10+)

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 18-1165 is a premium-quality tapered roller bearing designed for MerCruiser stern drive applications. This precision-engineered bearing serves as the upper drive shaft housing bearing, ensuring smooth operation and reliable performance in demanding marine environments.

Key Features:

  • Tapered roller bearing design for superior load distribution
  • Engineered to meet or exceed OEM specifications
  • Premium materials for extended service life in harsh marine conditions
  • Direct replacement for Mercury Marine OEM part 31-61100A1
  • Outside diameter: 1-15/16 inches

Fits MerCruiser Models:

  • MC-I stern drives
  • R and MR stern drives
  • Alpha One stern drives
  • Alpha One Gen II (serial number 0F679999 and below)
  • SS stern drives

Sierra products are manufactured to withstand the rigorous demands of marine applications, providing dependable performance season after season. This bearing is a critical component for proper stern drive operation and should be replaced during routine maintenance or rebuild procedures.

OEM Cross-Reference: Mercury Marine 31-61100A1, OMC 983891, GLM 21510, Mallory 9-75117

Petty good

check out with amazon was great

very quick and easy

Great prices, wish you had more in stock though... free shipping over 300.00 would be nice too...

Easy to use, looking forward to seeing what the shipping exp is going to be like

All good so far. Could be a little clearer about if the order will include needed any additionally needed hardware for install.

so far so good

Great Price, shipped 2 days later though.

Great Prices

Stuff I was looking for was easy to find and checkout was easy. All parts were for the vehicle i selected and fit perfectly.

Autoplicity is a fast & courteous place to do business.

I am impressed with they mail order service. Recommended.

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