Sierra 18-7986-1 Fuel Water Separator Filter Kit, Aluminum Tall Filter, 10 Micron, 3/8 Inch Pipe Plugs

The Sierra 18-7986-1 is a fuel water separator filter kit built around an aluminum tall filter housing rated at 10 microns. It is designed to protect gasoline-powered marine engines, including inboard, sterndrive, and outboard fuel injection systems, from water and particulate contamination in the fuel supply. The kit removes over 99.8% of emulsified water from gasoline and is over 90% efficient at capturing particles as small as 10 microns, keeping fuel clean before it reaches the engine. It is rated to flow at 90 GPH, enough capacity to feed high-demand engines without restricting fuel delivery.

The 18-7986-1 kit includes a replacement filter element (18-7945), a mounting bracket (18-7775), and two 3/8 inch pipe plugs (18-4264) for installation. The aluminum housing offers a durable, corrosion-resistant alternative to the stainless steel version of this same tall filter design. This kit does not include a drain bowl; it is intended for standard filter-and-bracket mounting rather than a drainable bowl assembly.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-7986-1
• Kit Type: 3/8 Inch Aluminum (Tall Filter)
• Filter Rating: 10 Micron
• Outer Material: Aluminum
• Pipe Plug Size: 3/8 Inch
• Filter Element Included: 18-7945
• Bracket Included: 18-7775
• Pipe Plugs Included: 2 x 18-4264 (3/8 Inch)
• Flow Rate: 90 GPH
• Water Removal Efficiency: Over 99.8% of emulsified water
• Particle Filtration Efficiency: Over 90% at 10 microns
• Weight: 2.32 pounds
• UPC: 808282203269

Frequently Asked Questions

What is included in the Sierra 18-7986-1 fuel water separator kit? The 18-7986-1 kit includes a 10 micron filter element (18-7945), a mounting bracket (18-7775), and two 3/8 inch pipe plugs (18-4264).

What micron rating does this filter use? The 18-7986-1 uses a 10 micron filter element that is over 90% efficient at removing particles as small as 10 microns.

How much water can the 18-7986-1 remove from fuel? It removes over 99.8% of emulsified water from gasoline before it reaches the engine.

What is the flow rate of this fuel filter kit? The Sierra 18-7986-1 flows at 90 GPH, enough to supply fuel to high-demand marine engines.

Is the 18-7986-1 housing aluminum or stainless steel? The 18-7986-1 uses an aluminum tall filter housing. A stainless steel version of the same tall filter design is sold under a different Sierra part number.

What size pipe plugs come with this kit? The kit includes two 3/8 inch pipe plugs, part number 18-4264.

What engine types is this fuel water separator designed for? The 18-7986-1 is designed to protect gasoline inboard, sterndrive, and outboard fuel injection systems from water and particulate contamination.

Does the 18-7986-1 kit include a drain bowl? No, the 18-7986-1 kit includes only the filter, bracket, and pipe plugs; it does not include a drain bowl assembly.

How much does the Sierra 18-7986-1 filter kit weigh? The 18-7986-1 fuel water separator kit weighs 2.32 pounds.

What is the replacement filter element for the 18-7986-1? The replacement filter element used in the 18-7986-1 kit is Sierra part number 18-7945.

Is the Sierra 18-7986-1 a genuine Sierra part? Yes, 18-7986-1 is the genuine Sierra part number for this aluminum tall filter fuel water separator kit.

How is the 18-7986-1 different from the stainless steel tall filter kits? The 18-7986-1 uses an aluminum housing, while Sierra also offers 1/4 inch and 3/8 inch stainless steel tall filter kits as separate part numbers with the same 10 micron filter element but different brackets and pipe plug sizes.