How to Install a Marine Fuel Water Separator on Your Boat

Bad fuel can quickly turn a dream day out on your boat into a nightmare experience of being stranded and waiting for a tow.

Up to 87% of people stated that they have had issues with their boat’s engine because of poor fuel quality or water in the fuel system. Issues with fuel are unfortunately common if you don’t have the right filtering equipment.

Thankfully there are tools and equipment that can help you to keep your boat’s engine running smoothly every time you’re out on the water.

Keep reading to learn all about how to install a marine fuel water separator and the benefits of having one installed on your boat.

What Is a Marine Fuel Water Separator?

A marine fuel water separator is a device that works to make sure the fuel delivered to your boat’s engine is clean. Its primary function is to remove contaminants and water from your fuel before it enters the engine.

Unfortunately, water and other contaminants can harm components of your boat’s engine, shortening the engine’s service life and leaving you with costly repairs.

There are a variety of fuel water separators, such as the Suzuki marine fuel water separator, and the R12T diesel water separator. Knowing your fuel system requirements can help you pick the right marine fuel water separator for your marine application. Refer to our other blog “Your Diesel Water Separator, Explained” for a detailed explanation of the inner workings of a fuel water separator.

How Does a Marine Fuel Water Separator Work?

Finding the best marine fuel water separator for your boat is important for the longevity of your engine. But how does a marine fuel water separator work?

A fuel water separator not only helps to remove contaminants and debris from your fuel before it reaches the engine, it also removes any water found in your fuel. As fuel enters the fuel water separator, it passes through a filter media (typically 10 microns). This filter removes over 99 percent of the particulates in the fuel and acts as a barrier to any water inherently found in the fuel. Because water is denser than gas, the water sinks to a collection bowl at the bottom of the filter and is retained there. Depending on amount of fuel consumption and the humidity in your local environment, you should view the water level in the drain bowl and drain it at least weekly. If the bowl contains any water, open the valve at the bottom of the drain bowl and drain the unwanted water into a container for proper disposal.

How to Install a Marine Fuel Water Separator

There are important steps and precautions to take when installing your marine fuel water separator on your boat.

Be sure to follow these steps to make your installation process as easy and seamless as possible.

1. Arrange Your Tools

Before beginning the installation process, it is important to know what supplies you’ll be needing. Here are some of the recommended basics for installing a marine fuel filter water separator:

  • A marking tool for marking the mounting hole locations
  • An electric drill for making holes for the separator mount
  • A drill bit for making the mounting holes
  • Open-end wrenches
  • Crescent wrench
  • Pliers
  • A variety of screwdrivers
  • A pocketknife or box knife
  • A roll of Thread seal tape
  • The necessary mounting screws, washers, and bolts
  • A simple First Aid kit incase there is an accident

2. Safety Precautions

Another important step to take is to ensure you have taken all the necessary safety measures to prevent spilled fuel or, worse yet, a fire. When installing your filter, remember gasoline is a very highly flammable substance. Make sure the engine to your device is turned off, the engine and surrounding components are cool to the touch, and you have the necessary fire suppression equipment nearby in case there are any mishaps. Keep heat, sparks, and flame away from the filter and clean up any spills immediately.

3. Marine Fuel Water Separator Placement

Once you have all of your tools together and have taken the necessary safety precautions, it is time to find the best location to place your marine fuel filter water separator.

The most important thing about placement for the marine fuel water separator is that it must be accessible. You’ll need to see the amount of water in the drain bowl, and you will need to be able to reach under the drain bowl and open / close the drain plug to drain the water. Also, you will need to have sufficient clearance to replace the filter element.

Install the filter above bilge water, between the fuel tank and engine (or primer bulb if on an outboard). The hoses should reach the filter and onward to the engine without kinking or making sharp turns.

4. Make Your Markings

Once you’ve decided on a location to install the marine fuel water separator, you’ll need to make marks on the installation points. Then use your drill to create holes for mounting the fuel water separator.

It is important to remember that the fuel water separator needs to be placed vertically in order to function properly.

5. Install the Separator

Now that you have the holes drilled you can mount the separator onto your boat. Line up the holes on the die cast cap or mounting bracket with the holes that you drilled.

Use bolts or screws to hold the separator in place, depending on the fixing method of your preference. Now that the separator is in place, it’s time to install the hoses.

6. Install the Hoses

Install barb fittings into the die cast cap filter housing, and don’t forget to put thread seal on the fitting threads. Also, be sure to place a fuel collection container under the separator to collect any discharged fuel when cutting the fuel line.

Cut the fuel line and attach the end of the fuel line from the gas tank onto the barb-fitting on the input side of the filter. Take the other side of the fuel line and attach it to the barb-fitting on the output side of the filter. Note, you should use jubilee clips to secure the fuel lines onto the barb-fittings.

7. Priming the Separator

The next step will involve priming the separator. Gently remove the filter element from the mounting cap and fill the filter with gas. Note, the filter drain bowl will remain on the filter element during this process. Re-attach the filter element to the mounting cap and wipe the entire unit clean.

Before starting the engine, give everything one more look over just to make sure that everything was installed correctly and there aren’t any missing parts or loose attachments.

8. Start Your Engine

Now that everything is hooked up and looking good, it is time to test it out. Begin by starting your boat’s engine. Continue checking for any fuel leaks from the separator or the engine.

This is a pre-check prior to taking your boat out for a sea test. Once you are out on the open water you should give your boat a test with the throttle wide-open and re-check for any leaks.

Save Your Engine, Get a Fuel Water Separator

Marine fuel water separators are a great investment for prolonging the life of your boat’s engine and for saving you money in the long run. You’ll have a more fuel-efficient boat with better performance.

Don’t let engine problems ruin your next day out on the water. Make the most of your time with friends and family on the boat that you love. Click here and get your marine fuel water separator today. Also, you can click here to refer to the detailed mounting instructions on our website.