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Sierra 18-99116 Water Pump Gasket Replaces Yamaha 6G1-45315-A0

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

18-99116
08/04/2036 6:54 PM
Sale Price

$9.18

1 left at this price

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-99116 is a replacement water pump gasket engineered to replace OEM Yamaha part number 6G1-45315-A0. This gasket provides a reliable, leak-free seal at the water pump base on compatible Yamaha outboard engines, helping maintain proper cooling system function and protecting the engine from overheating.

Key Features:

  • Direct replacement for Yamaha OEM part 6G1-45315-A0
  • Designed to meet or exceed original equipment specifications
  • Ensures a proper seal at the water pump base to prevent coolant leaks
  • Manufactured by Sierra International, a trusted name in marine replacement parts
  • Ideal for use during routine water pump impeller service intervals

OEM Cross-Reference: Replaces Yamaha 6G1-45315-A0 / 6G1-45315-A0-00

Sierra's marine-grade gaskets are built to withstand the demanding conditions of outboard engine cooling systems. Replacing the water pump gasket during impeller service helps ensure a proper seal and prolongs the life of your cooling system components.

Great online ordering. I found exactly what I wanted and had it ordered in less than 10 minutes from my PHONE!!! Simply wonderful!!!

Some items are not auto specific but when you enter the auto info it does not let you purchase the item

Great company to deal with. I placed an order with them (albeit an incorrect shipping address) and before you know it I'm expecting delivery in a very short amount of time. I also did have to call and attempt to correct my address error when the customer service rep let me know that all is well and set to be delivered to the correct address. I appreciate the fact that the gentleman on the other end of the phone was reassuring, courteous, and professional. I'd certainly do business with them again as the prices and customer service can't be beat!

Fast and easy, looking forward to installing them. Big Mopar head, huge Dakota fan, driver.

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Item just as descibed, great price and fast shipping. This has been my first order and actually first time searching for an auto part on this site and all went as expected. Glad I saw reference to it a car forum.

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I'm a little concerned. The Fabtech part number doesn't match the correct description. I need the impact tube rear mount not the bushing kit. I talked to a representative and he said if I used the Fabtech number I would get the correct part.

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