Sierra 78866 Fuel Element Assembly

Sierra 78866 Fuel Element Assembly (47-78866) is a bowl-style fuel filter element designed to help protect your engine by trapping contamination and allowing water to be drained to support longer filter service life. It features Sierra AquaVue clear bowl options for outboard/above-deck installations, and a metal bowl collection for below-deck flame-resistant requirements.

Key Features

• Helps extend fuel filter service life by allowing water to be drained from the filter
• Bowl-style fuel filter design for marine fuel system protection
• AquaVue clear bowl option for outboard and above deck installations
• Metal Bowl Collection option meets USCG flame-resistant requirements for below deck use

Product Compatibility

• Marine gasoline outboard fuel systems
• Marine inboard/auxiliary engines where a bowl-style fuel element assembly is used
• General engine fuel filtration/maintenance applications (verify exact filter head/bowl compatibility)

Product Details

• Product: Sierra 78866 Fuel Element Assembly
• SKU/Variant: 47-78866
• Type: Fuel element assembly (fuel filter)
• Purpose: Fuel filtration with water drain capability to help support longer service life
• Bowl guidance: AquaVue Clear Bowls are intended for outboard and above deck installations; Metal Bowl Collection is used where USCG flame-resistant metal bowls are required below deck

Parts Desk Insights

Best Use Case: Best for routine fuel filter element replacement when you want to maintain filtration performance and retain the ability to drain accumulated water.

Common Issues: Most common service issues are incorrect bowl/head pairing and delayed water drainingconfirm the filter assembly diagram and replace any associated seals/gaskets during service per your engine/fuel filter head instructions.

Related Products & Accessories

• Browse Fuel Filters – Find related Sierra fuel filter elements, bowls, and service parts for your fuel/water separator setup.