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Sierra 18-70932 MerCruiser Thermostat Cover to Starboard Manifold Molded Water Hose

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

70932
08/05/2036 12:50 AM
Sale Price

$31.09

3 left at this price

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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 18-70932 is a precision-molded replacement water hose designed for MerCruiser stern drive engines. This hose connects the thermostat cover to the starboard exhaust manifold, playing a critical role in the engine's raw water cooling system. It is a direct OEM-quality replacement for MerCruiser part numbers 32-87117 and 32-871171.

Key Features:

  • Pre-formed molded construction for precise, leak-free fit
  • Dual-diameter design: 1" (25mm) and 13/16" (21mm) I.D. ends
  • Direct replacement for MerCruiser OEM part numbers 32-87117 and 32-871171
  • Also interchangeable with Mallory part number 9-44059
  • Meets or exceeds original equipment specifications
  • Engineered for durability in demanding marine cooling system environments

This Sierra molded hose is a trusted aftermarket solution for maintaining the cooling integrity of MerCruiser 4.3L, 5.0L, and 5.7L V6 and V8 engines (305 & 350 CID). Sierra's marine engine parts are manufactured to OEM tolerances, ensuring a proper fit and reliable long-term performance.

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Awesome first time buyer,but not last Thanks for the awesome prices

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Your competitive pricing won my business through the internet and I wasn't disappointed. The price was great ( about 1/2 MSRP) and item was shipped very quickly. No backorder problems here! I was impressed with the quality of my H pipe and with the packaging.

I am not happy with my back rack, it arrived all scratched up and I would like a replacement one, I will ship this one back but I am not going to pay for shipping. Please contact me on how u want to handle this. Tim Sullivan

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Thank you! You were the cheapest and your service rocked! Got my item in less than a week.

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