Sierra Engine Parts

Sierra 18-78867 78867 Fuel Water Separator Kit

SKU: 4003787 · UPC: 808282386269 · MPN: 18-78867
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02 · Overview

Sierra 18-78867 78867 Fuel Water Separator Kit — Product description

Keep your marine engine running smoothly with the Sierra 18-78867 Fuel Water Separator Kit from Sierra Engine Parts. Designed as a reliable replacement for OEM fuel filtration systems, this kit effectively removes water, dirt, and contaminants from your boat's fuel line, preventing corrosion, injector damage, and costly breakdowns on the water. Whether you're powering through rough seas or cruising calm bays, this kit ensures clean fuel delivery for peak performance.

Key Features of the Sierra 18-78867 Kit

  • High-Efficiency Filtration: Captures microscopic water droplets and particulates, safeguarding your engine's fuel system.
  • Durable Construction: Built to withstand harsh marine environments, including vibration, corrosion, and extreme temperatures.
  • Easy Visual Inspection: Transparent options allow quick checks without disassembly.
  • USCG Compliant Options: Choose the right bowl type based on your installation location for full regulatory adherence.
  • Universal Fit: Compatible with a wide range of outboard and sterndrive engines, making it a go-to choice for boat owners and mechanics.

AquaVue™ Clear Bowls for Above-Deck Flexibility

Opt for the innovative AquaVue™ clear bowls when installing outboards or above-deck systems. These transparent bowls let you monitor fuel condition at a glance, spotting water accumulation or filter clogs instantly. Ideal for easy maintenance during routine checks, they combine visibility with robust polymer construction that resists cracking and UV degradation.

Flame-Resistant Metal Bowls for Below-Deck Safety

For installations below deck, switch to the metal bowl collection to meet United States Coast Guard (USCG) regulations. These flame-resistant bowls provide superior fire safety while maintaining excellent filtration performance. Their rugged aluminum or steel builds handle high-pressure fuel lines and offer long-term reliability in confined, engine-room spaces.

Simple Installation and Maintenance Tips

Installing the Sierra 18-78867 kit is straightforward for DIY boaters or pros. Begin by shutting off fuel supply and relieving system pressure. Remove the old separator, attach the new assembly using provided O-rings and fittings, and prime the system before startup. Always match hose sizes and secure connections to avoid leaks.

To maximize lifespan:

  1. Inspect bowls monthly for water buildup—drain via the petcock valve.
  2. Replace filters every 100 hours of operation or annually.
  3. Flush the system if switching fuel types.
  4. Store spares in a dry place to prevent seal degradation.

Pro tip: Pair with a secondary filter for ultimate protection in diesel applications, extending engine life and reducing downtime.

Why Boaters Trust Sierra 18-78867 Fuel Water Separators

Sierra Engine Parts stands out for precision engineering that matches or exceeds OEM specs, without the premium price tag. This kit has earned rave reviews from saltwater anglers, yacht owners, and commercial operators for its consistent performance in real-world conditions. By preventing water-related issues like rough idling, hesitation, or complete failure, it saves you from emergency tows and repair bills.

Frequently Asked Questions

What makes the Sierra 18-78867 Fuel Water Separator Kit essential for boats?

It removes water and debris from fuel, protecting injectors and carburetors from damage, which is crucial in humid marine environments where condensation is common.

When should I use AquaVue™ clear bowls with this kit?

AquaVue™ clear bowls are perfect for outboard motors and above-deck setups, offering easy visual checks for water separation without tools.

Why are metal bowls required below deck?

USCG rules mandate flame-resistant metal bowls in below-deck areas to minimize fire risks from potential fuel leaks or sparks.

How often do I need to service the Sierra 18-78867 kit?

Drain water monthly, replace elements every 100 hours or yearly, and inspect fittings seasonally for optimal performance.

Is this kit compatible with most marine engines?

Yes, it fits a broad range of outboards and inboards as an OEM alternative, but always verify hose and mounting specs for your model.

Can this prevent common fuel-related engine problems?

Absolutely—it eliminates water-induced issues like stalling, poor acceleration, and corrosion, keeping your engine reliable season after season.

What if I notice water in the bowl after installation?

Drain it immediately via the valve, check fuel source for contamination, and monitor—it's normal separation working as intended.

AquaVue™ Clear Bowls: Use for outboard and above deck installations.
Metal Bowl Collection: USCG regulations require the use of flame resistant metal bowls below deck.


SKU: NVN-4003787
MPN: 18-78867
UPC: 808282386269
03 · The numbers

Technical specifications

BrandSierra Engine Parts
ModelSierra 18-78867 78867 Fuel Water Separator Kit
SKU / MFR#4003787

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04 · Before you buy

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05 · Customer voices

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