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Sierra 18-4456 Marine Exhaust Protector Valve 3 Inch

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

118-4456
06/03/2036 3:49 AM
Sale Price

$26.42

In Stock (5)

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Usually delivered within 2 days

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No Hassle Returns

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-4456 is a heavy-duty marine exhaust protector valve designed to prevent water and debris from entering your boat's exhaust system. This 3-inch flapper valve is essential protection against water surging into the exhaust during following seas, when maneuvering in reverse, or when waves hit the stern of your vessel.

Key Features:

  • Fits 3-inch (76.2mm) outside diameter exhaust tubes
  • Compounded rubber flapper valve construction
  • Weather-resistant EPDM material with UV stabilizer for long-lasting durability
  • External flapper design for reliable water shutoff
  • Includes stainless steel hose clamp for secure, corrosion-resistant installation
  • Meets or exceeds OEM specifications

Replaces OEM Part Numbers: MerCruiser 34765A1, 34765A2, GLM 89240, Mallory 9-44000

Applications: Designed for use on Chris-Craft inboards, Chrysler inboards, Crusader inboards, Pleasurecraft (PCM) Waukesha, and other marine inboard engines with 3-inch exhaust outlets. Also helps prevent birds and other debris from nesting in exhaust outlets when the boat is stored on a lift.

Quality product and fast delivery thanks again!

Everything went well. I'm not sure why a blower fan would be made with any metal that could corrode and yet that's what happened to the old one that is NOT that old.

Na

Shipping was extremely fast a on a hard to find Item, The price with free shipping was better than buying elsewhere with paid shipping I am very satisfied

Easy peasey

The price on the replacement lids was low enough to handle the shipping charge to provide a fair total price. Thx

No problems. Fast delivery. Good price.

It looks like it will work but I haven't had time to install it. Con: No directions

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