My Account
Shopping Cart

Sierra 18-4574 Outer Wear Plate for Yamaha Outboard Water Pump

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

18-4574
07/15/2036 2:05 AM
Sale Price

$9.81

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 18-4574 Outer Wear Plate is a precision-engineered replacement component for the water pump cooling system on select Yamaha outboard engines. Designed as a direct OEM replacement, this wear plate serves as a protective surface within the water pump assembly, helping maintain proper impeller function and coolant flow to keep the engine running at optimal temperatures.

Key Features:

  • Direct replacement for Yamaha OEM part number 6EG-G4323-00
  • Engineered to meet or exceed OEM fit, form, and function standards
  • Compatible with the Sierra water pump repair kit 18-4532 (without housing)
  • Works in conjunction with Sierra impeller 18-8911, cup insert 18-4547, and water pump gasket 18-99157
  • Manufactured by Sierra International, a trusted name in marine replacement parts

The 18-4574 is an individual outer wear plate sold as a single unit, making it ideal for targeted repairs or as a component replacement during a full water pump service. Regular inspection and replacement of water pump wear plates is essential for maintaining reliable engine cooling and preventing overheating damage.

Best price, shipped free and fast!!

I had been Surfing the Internet &amp; calling various Auto Parts Stores in the area for this particular part and finally I found the part on your web-site @ very reasonable price. I was also able to talk to your tech. rep. on the phone about the compatibility before placing the order ..

Quick and easy, thank you.

Fast / Easy Straightforward

great price

Easy checkout

.

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