18-7845 Long Fuel Filter/Water Separator, 21-Micron
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SIERRA18-7845 Long Fuel Filter/Water Separator, 21-Micron


In stock online.
Model # 378481 | Mfg # 18-7845UPC # 808282368975


18-7845 Long Fuel Filter/Water Separator, 21-Micron

Name Value
Type Fuel Filters

Product Overview

Industry leading fuel filter element for outboard and inboard engines with high fuel demands

High-performance fuel injected engines require ultimate water separation, fuel filtration and maximum fuel flow. Sierra's new filter elements deliver all three of these critical performance factors and are engineered for today’s sterndrives, inboards, and 2-cycle and 4-cycle outboards.

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. This filter offers 21 micron filtration and is ideal as a primary filter feeding a 10 micron or finer final filter to prevent it from loading up with course debris. 

Key Features

  • 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
  • Independently tested to JIS, SAE J1839/J905 and ISO 4548-12 standards
  • Epoxy coated interior to resist corrosion
  • Will not separate oil-gasoline mixture of 2-stroke fuel
  • Replaces Mercury 35-802893Q and 35-807172 and Yamaha ABB-FUELF-IL-TR 

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


  • Application: Gasoline
  • Filtration: 21 Micron
  • Fuel Flow: 90gph


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