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Sierra 18-6854 Battery Isolator 1-Alternator 3-Battery 160 Amp

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

18-6854
06/21/2036 6:47 AM
Sale Price

$353.24

2 left at this price

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-6854 battery isolator enables charging of up to three separate batteries from a single alternator source, making it ideal for marine vessels and RVs that require isolated battery banks for different electrical systems. This 160-amp rated isolator uses solid-state diode technology to prevent batteries from discharging into each other while ensuring all batteries receive a charge when the engine is running.

Key Features:

  • 160-amp maximum current capacity for reliable high-output charging
  • 1 alternator input with 3 battery output terminals
  • Solid-state diode design for automatic battery isolation
  • Prevents battery cross-discharge when engine is off
  • Maintains separate starting and house battery banks
  • Heavy-duty construction for marine and mobile applications

Important Compatibility Note: This isolator is not compatible with Delco "CS" style alternators. Verify your alternator type before installation to ensure proper operation.

Sierra battery isolators are engineered to withstand the harsh marine environment while providing dependable multi-battery charging performance for boats, RVs, and other vehicles requiring isolated electrical systems.

Products specifications

Amps

160

Application

1 alternator / 3 batteries

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easy, smooth transaction. Reasonably priced item. I was hesitant when reading some negative reviews, but took a chance anyway. I'm glad that I did. Item quickly received; no problems. Will buy from again.

The delivery service was total mess the boxes were damaged and one of the nuts was missing .

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very good

Would like an est arrival date

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Let me get the product first.

Best price I found on Weathertech digifit floor mats for my 2012 F150 Supercrew. Product was as described and shipping was fast too.

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Excellent service and the cheapest price that I could find anywhere. Ordered on a Sunday and delivered in record time three days later...basic overground shipping. I will deffinately order from here again!

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