18-7986-1 Fuel Filter/Water Separator Kit 3/8" Aluminum Tall
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SIERRA18-7986-1 Fuel Filter/Water Separator Kit 3/8" Aluminum Tall


In stock online.
Model # 9399478 | Mfg # 18-7986-1UPC # 808282203269


18-7986-1 Fuel Filter/Water Separator Kit 3/8" Aluminum Tall

Name Value
Type Fuel/Water Separators

Product Overview

Industry leading fuel filter assembly for high horsepower outboards

High-performance fuel injected engines require ultimate water separation, fuel filtration and maximum fuel flow. Sierra's fuel filter assemblies deliver all three of these critical performance factors and are engineered for today’s 2-cycle and 4-cycle outboards. The aluminum filter head is compact, coated to resist corrosion and features 3/8" ports. Its compact design, make it ideal for installations in space limited locations

Ethanol-blended fuels hold more water and can increase the chances of water in fuel tanks, resulting in premature wear, poor performance and component damage. Sierra 7800 Series fuel filters are designed to successfully remove 99% of the emulsified water found in fuels. Contaminants over 10 microns can cause severe damage in close tolerance modern fuel pumps and injectors; Sierra filters have 90% efficiency rate of removing these harmful contaminates while maintaining fuel flow rates to meet the demands of modern high performance engines.

Key Features

  • Compact filter head design is ideal for tight locations
  • Filter elements remove 99% of emulsified water from fuel
  • Designed to be an exact fit and meet specifications of OEM canister filters
  • 90% efficient at removing particulate contamination
  • Maintains fuel flow while filtering harmful water and debris
  • Filters independently tested to JIS, SAE J1839/J905 and ISO 4548-12 standards
  • Included filter (18-7866) replaces Yamaha MAR-FUELF-IL-TR and Mallory 9-37807

See our Engine Parts Selector to confirm this fitler assembly is right (or to find the correct one) for your application.


  • Application: Gasoline
  • Filtration: 10 Micron
  • Fuel Flow: 90gph


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