5 Top Tips For Choosing a Fuel Water Separator

Most fuels have contaminants. This could be small pieces of debris, metallics, and more often than not, water. Either way, every effort to remove all contaminants should be made before the fuel is used. Removing water and solid particles from fuel requires fuel filter water separators.

By removing water and impurities, engines are more efficient and have a longer lifespan. If these contaminants reach certain parts of the combustion chamber this can cause engine failure.

What is a fuel water separator? It is a device fitted into the fuel system, that works to ensure the fuel being delivered to the engine is free of contaminants, and of any water. These devices filter the fuel, and separates the water from the fuel before it reaches certain sensitive engine components.  The clean fuel is delivered to the engine, and the water is contained in a collection bowl at the bottom of the filter.

Where are fuel water separators used? Engines of all sorts, marine, industrial, and agricultural industries use fuel water separators.

Does your engine need a new fuel water separator? It can be daunting choosing the right filter for your application, but you should consider the following when making this decision.

Which Fuel Water Separator Should I Use?

Any engine, whether using gas or diesel as a fuel, needs some form of protection from pollutants within the fuel. A fuel filter plays an integral part in protecting the engine with its filtration system. But, a water separator must supplement this system.  Filters operate in harsh environments, and therefore filters will eventually clog up. once clog they become inefficient and, over time they will lose their filtering capabilities.  This is why fuel water separators and particle filters need to be replaced regularly to prevent machinery failure.

Any engine, whether using gas or diesel as a fuel, needs some form of protection from pollutants within the fuel. A fuel filter plays an integral part in protecting the engine with its filtration system. But, a water separator must supplement this system.

Here are five tips in choosing replacement Fuel Water Separators and Filters.

1. The Filter Element

10-micron filter element

A fuel filter is an in-line device for any engine using fuel, be it gasoline or diesel.

There are different filters for different applications. When fuel passes through the filter media, the filter “catches” dirt particles. The size of the pores in the filter determines the size of the particles that it captures.  We call this “micron level” and is available in 2, 10, or 30 microns, indicating the size of the particles it will catch. Most marine and industrial systems utilize a 10- and 30-micron filters between the fuel tank and the engine.

For sensitive performance systems, a secondary two micron filter can be installed downstream from the primary filter for additional protection.

2. The Inspection Bowl

Off-center Drain Bowl Assembly

It is common to find water in fuel. This is due to many facets like condensation and pollutants found in the fuel. To diminish damage and increase efficiency water and pollutants should be removed from this fuel.  We use a separation system to do this.

The fuel water separator uses a pleated filter media. This filter catches water particles and makes them into bigger droplets. These droplets are heavier than the fuel and will then fall into a collection bowl at the bottom of the filter.

The collection bowl comes in many forms. Bowls may be made of clear plastic, aluminum, or a combination of both – a clear bowl with an aluminum heat shield for protection from the hot engines. Filters with clear collection bowls should not be used in an enclosed engine compartment.  Often the heat in the engine compartment is very high and the plastic materials are not rated for these temperatures.  Collection bowls can be reused several times before they need to be replaced.

All collection bowls have some type of drain plug, which is used to empty the water from the collection bowl. Draining the water from these bowls from time to time is a must.  This ensures the proper operation of your filter. Clear bowls are easier to use; as you can see the water level in the bowl to determine the timing of the draining.  Metal drain bowls are not as easy to determine when to drain the water.  Filters with metal drain bowls should be drained every few days to ensure the proper operation of the filter.

3. The Fuel Flow Rate

Fuel-flow rate is critically important when selecting a fuel water separator. Always check back with the engine manufacturer for the correct size filter for your fuel water separator.

Typically, the larger the engine, the larger your fuel water separator should be. As a general rule of thumb, the required flow rate of your fuel water separator is about 10 percent of the rating of your engine. So for example, a 200-hp engine would require a 20-gallons-per-hour (GPH) filter. Our CFS1020 diesel separator cleans your fuel at 20 GPH.

The typical formula for average fuel usage at gallons per hour (GPH) is to divide horsepower by 10:

Horsepower (HP) ÷ 10 = Gallons-Per-Hour (GPH)

So a boater with a four-stroke, 250-hp marine outboard engine with a fully open throttle is using 25 GPH.

Consumption is what your engine burns, flow is what has to move through the system; many engines have a system that sends fuel back to the tank. Make sure the water separator you choose has the correct flow specification.

4. Engine Size

Simply stated, bigger engines need bigger separators.  The same goes for smaller engines they need smaller separators.

This is because the flow rates are different. Think of flow as a volume. Smaller separators have lower flow and the opposite for larger separators.

When replacing the separator a quick visual check of the comparative size will give you an early head’s up.

5. Environmental Applications

Your selection of a fuel water separator should also be based upon the type of environment the filter is expected to perform in.  Moderate environmental conditions such as mild climates and moderate usage of these systems may not require fuel water separators.  However, in harsher environments it is highly recommended to use a fuel water separator.

In harsher environments such as construction sites or heavily soiled environments, excessive dirt and debris often finds its way into fuel storage systems.  In turn, the engines in these environments are subject to this contaminated fuel.

In high humidity environments such as coastal regions, areas with high levels of precipitation, or regions with humidity levels above 50% should use a fuel filter water separator.  These environments facilitate the collection of water vapors and droplets in the fuel system, and without the proper removal of these water contaminants, severe engine damage can occur.

Less Water Less Headache

When engines fail it is usually costly. Relative to the expense of major engine rebuilds; filters and water separators are cheap. For smaller domestic engines replacing filters and separators is often a do-it-yourself job. Whether you’re looking for an outboard fuel water separator or a diesel fuel water separator, our fuel filter water separators  are compact, versatile, and fully configurable.

Many insurers will insist on evidence of scheduled replacement of consumable items such as filters and fuel water separators.

For peace of mind consult an expert. There are often other issues that may be causing too many frequent replacements of filters. If the filters are clogging up very quickly you need to have an expert take a look into the fuel tank.  You may have large amounts of deposits that need to be cleaned out.

Head on over to our Clear Flow Filtration Systems section to learn more about our quality & value, and for more information on purchasing, replacing, and maintaining your fuel water separator.