Water Separarting Filters | Johnson Evinrude

Specifications

OEM & Cross Reference Numbers

Universal Marine Application

Sierra 18-7920 is a universal replacement fuel / water separator filter for compatible marine filter heads using a 1"-12 threaded filter.

Because this filter is used across multiple marine engine brands and fuel systems, fitment should be determined by the filter-head thread and the existing filter cross-reference number rather than by engine horsepower alone.

What a Fuel / Water Separator Does

A marine fuel / water separator helps protect the engine fuel system by removing water and particulate contamination before the fuel reaches the engine.

Water can enter a marine fuel system through condensation, contaminated fuel or moisture in the tank. The separator provides an additional stage of filtration before the engine-mounted fuel filter or fuel injection system.

10-Micron Filtration

The Sierra 18-7920 is rated at 10 microns, allowing it to capture fine fuel contaminants while separating water from the fuel supply.

Maintaining a clean fuel / water separator can help reduce the chance of restricted fuel flow and contamination reaching carburetors, fuel pumps or fuel injection components.

When Should a Fuel / Water Separator Be Replaced?

Replacement intervals vary based on engine use, fuel quality and operating conditions. Fuel / water separator filters should be inspected and replaced as part of regular marine engine maintenance.

Replacement should also be considered whenever contaminated fuel or water in the fuel system is suspected.

Common Reasons for Replacement

• Routine annual or seasonal maintenance
• Water found in the fuel system
• Contaminated or stale fuel
• Restricted fuel flow
• Engine fuel starvation symptoms
• Unknown age of the existing fuel separator
• Replacing Fram CH33APL
• Replacing Johnson / Evinrude or OMC 771839
• Replacing Mercury 35-809099
• Replacing Racor B32014 or S3214

Installation Notes

Confirm that the filter head uses the correct 1"-12 thread before installation.

Follow the engine or filter-head manufacturer's installation procedure. Inspect the filter-head sealing surface and make sure the old filter gasket has been completely removed before installing the replacement.

Key Features and Benefits

• Sierra marine replacement fuel / water separator
• Sierra part number 18-7920
• 10-micron filtration rating
• 1"-12 thread pitch
• Large center-hole configuration
• Spin-on replacement design
• Universal marine application
• Replaces Fram CH33APL
• Replaces Johnson / Evinrude 771839
• Replaces OMC 771839
• Replaces Mercury 35-809099
• Replaces Racor B32014
• Replaces Racor S3214
• Helps remove water and contaminants from marine fuel

FAQ

What is the micron rating of Sierra 18-7920?
The Sierra 18-7920 is a 10-micron fuel / water separator.

What thread does Sierra 18-7920 use?
It uses a 1"-12 thread.

Is this the large-hole fuel / water separator?
Yes. Sierra 18-7920 is the large center-hole configuration.

Is Sierra 18-7920 a spin-on filter?
Yes. It is a spin-on replacement fuel / water separator.

What Mercury filter does Sierra 18-7920 replace?
It cross references Mercury Marine 35-809099.

What Johnson / Evinrude or OMC number does it replace?
It replaces 771839.

What Racor filters does it replace?
It cross references Racor B32014 and S3214.

What Fram filter does it replace?
It cross references Fram CH33APL.

Is this filter engine-specific?
No. It has a universal marine application for compatible filter heads using the correct 1"-12 thread.

How do I know if this filter fits my boat?
Compare the existing filter part number and verify that your filter head uses a 1"-12 thread. Cross-reference numbers are listed above.

Searchable Terms

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