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Sierra 18-1908 Manifold Riser Spacer 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

18-1908
06/04/2036 10:08 AM
Sale Price

$164.52

In Stock (10+)

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Usually delivered within 2 days

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FREE SHIPPING

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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 18-1908 Manifold Riser Spacer is a 3" riser extension designed for marine exhaust systems on MerCruiser stern drive engines. These Sierra extensions provide the extra height to prevent water from traveling back into the riser when throttling down and can also provide additional clearance for exhaust hose routing.

Key Features:

  • Manufactured as a direct replacement and fully interchangeable with OEM products, primed and painted for added durability
  • Machined mating surfaces that eliminate additional preparation to establish a proper seal
  • Leak tested prior to paint to ensure quality
  • Special casting techniques create uniform wall thickness
  • Ready to install out-of-the-box

This riser spacer is compatible with GM based V6 carb and TBI engines with 2 piece exhaust manifolds. Use with Manifold 18-1952-1, Exhaust Elbow Mounting Kit 18-8554 and 18-8555, or Manifolds 18-1953-2 and 18-1957-1. Note: This is the spacer only; complete kit with mounting hardware and gaskets is available separately as part number 18-1908K.

Products specifications

Application

Mercruiser GM V6 229 and 262 CID (models 185 and 205), GM small block V8, 305-350 CID (models 200, 228, 230, 260 and 898), GM big block V8, 454 CID (models 330, 340 and 7.4L). Use with manifold 19521, 19531, 19571

Replaces

Mercruiser 93320

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Very easy transaction. Website easy to navigate. Order shipped the next day. Pleasure to do business with!<br><br>

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