Best Fuel & Water Separators of 2026

Robert Reyes Avatar
Robert Reyes
Last Updated: Jan 9, 2026

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Fuel & Water Separators are essential components for any boat or marine vessel that runs on diesel fuel. These products are designed to remove water and other contaminants from the fuel before it reaches the engine, ensuring optimal performance and preventing damage. Fuel & Water Separators come in a variety of sizes and styles to fit different types of boats and engines. They feature high-quality filtration systems that effectively remove water, dirt, and other impurities from the fuel, providing reliable and efficient operation for the vessel. These products are a must-have for any boat owner who wants to protect their investment and ensure a smooth and safe boating experience.

At a Glance: Our Top Picks

EVIL ENERGY 300ml Universal Oil Catch Can Kit Cover #TOP 1
EVIL ENERGY 300ml Universal Oil Catch Can Kit
ftb score rating icon 9.8
EVIL ENERGY 300ml Aluminum Oil Catch Can Cover #TOP 2
EVIL ENERGY 300ml Aluminum Oil Catch Can
ftb score rating icon 9.7
Caterpillar Fuel Water Separator Cover #TOP 3
Caterpillar Fuel Water Separator
ftb score rating icon 9.5

Top 10 Fuel & Water Separators

#TOP 1

EVIL ENERGY 300ml Universal Oil Catch Can Kit

KT01300BK-AMZ1
Black
2.6 FT
EVIL ENERGY 300ml Universal Oil Catch Can Kit Cover
EVIL ENERGY Oil Catch Can, Universal Baffled Catch Can Kit with Breather Filter, 300ml Aluminum Air Oil Separator Tank NBR Fuel Hose Kits for PCV System

The EVIL ENERGY Oil Catch Can is designed to fit most vehicles, giving you the flexibility to install it without worrying about space. It comes with a 300ml aluminum tank and a 2.6-foot hose, making it easy to set up and connect to your car’s PCV system. You can choose to use it with the breather filter for cars without a PCV system, helping to vent gases safely, or install it without the filter between PCV hoses to seal the system. Just keep in mind to clean the catch can regularly in cold weather to prevent moisture buildup and freezing, ensuring your engine runs smoothly.

What We Like
Universal compatibility
300ml aluminum tank
Flexible breather filter option
Includes 2.6ft hose
#TOP 2

EVIL ENERGY 300ml Aluminum Oil Catch Can

EV01298BK-CA
Black
2.6 FT
EVIL ENERGY 300ml Aluminum Oil Catch Can Cover
EVIL ENERGY Oil Catch Can, Universal Baffled Catch Can Kit with NBR Fuel Hose, 300ml Aluminum Air Oil Separator Tank for PCV System

The EVIL ENERGY Oil Catch Can offers a smart solution to keep your engine clean and running smoothly. Its baffled design, with a removable insert and steel wool, traps oil and moisture efficiently, helping you avoid carbon buildup. The 300ml tank fits most vehicles, giving you flexibility as long as you have enough installation space. The included NBR fuel hose is tough and heat-resistant, ensuring a durable and secure connection with its threaded ports. Whether your car uses a PCV system or not, this catch can adapts to your setup, improving your engine’s ventilation or sealing the system as needed for better performance.

What We Like
Effective oil and moisture trapping
Universal 300ml capacity
Durable heat-resistant NBR hose
Compatible with PCV systems
#TOP 3

Caterpillar Fuel Water Separator

CAT
175-2949
Pack of 1
Caterpillar Fuel Water Separator Cover
Caterpillar 175-2949 Advanced High Efficiency Fuel Water Separator

The Caterpillar 175-2949 Advanced High Efficiency Fuel Water Separator is a genuine CAT product designed to remove water and other impurities from your vehicle's fuel system. With a thread size of 1-14, a height of 185mm, and a diameter of 93mm, it is specifically designed to fit your vehicle. This modern-style fuel water separator is an essential component of your vehicle's fuel system that helps to prevent engine damage, improve fuel efficiency, and reduce emissions.

What We Like
Genuine CAT product
Designed to remove water and impurities from fuel system
Improves fuel efficiency, reduces emissions
#TOP 4

EVIL ENERGY Oil Catch Can for F-150 & Raptor

EV07385BK
F-150
EVIL ENERGY Oil Catch Can for F-150 & Raptor Cover
EVIL ENERGY Oil Catch Can, Air Oil Separator Compatible with 2011-2025 F-150 5.0L 2017-2023 Raptor 2018-2021 Expedition 3OZ

The EVIL ENERGY Oil Catch Can is designed to fit a wide range of Ford trucks, including F-150 and Raptor models from 2011 to 2025. It helps keep your engine clean by catching oil vapors and contaminants, which can extend your engine’s life and improve performance. The catch can uses a fine mesh aluminum filter to trap even tiny oil particles, ensuring precise filtration. Installation is straightforward thanks to custom brackets, hoses, and fittings tailored for your engine layout, so you won’t need extra adapters or modifications. This makes the EVIL ENERGY Oil Catch Can a convenient and effective upgrade to protect your engine.

What We Like
Wide vehicle compatibility
Effective oil vapor capture
Fine mesh aluminum filter
Custom-fit installation kit
#TOP 5

Caterpillar Fuel Water Separator 256-8753

CAT
2568753
Pack of 1
Caterpillar Fuel Water Separator 256-8753 Cover
Caterpillar 2568753 Fuel/Water Separator, 1 Pack

Caterpillar Fuel Water Separator 256-8753 is an excellent choice for customers who need to separate fuel and water. With an efficiency rating of Advanced Efficiency, it can remove more impurities from fuel and water. As a primary filter, it is designed to protect the engine and prolong the lifespan of the fuel system. The separator has a diameter of 93.0 MM, which can fit most fuel systems. The exterior is painted, which makes it more durable and resistant to corrosion. The product is packed with one separator.

What We Like
Advanced Efficiency rating for better impurities removal
Primary filter design to protect the engine and prolong lifespan of fuel system
Painted exterior for durability and corrosion resistance
#TOP 6

WIX Filters - Heavy Duty Fuel Water Separator

Wix
33472
WIX Filters - Heavy Duty Fuel Water Separator Cover
WIX Filters - 33472 Heavy Duty Spin On Fuel Water Separator, Pack of 1

This Fuel & Water Separator by WIX Filters is an easy-to-install and maintain product that features a pleated paper filter and a mesh support screening. Its highly durable and reliable design includes a drain plug for convenient maintenance.

What We Like
Durable and reliable
Convenient maintenance with a drain plug
Easy to install
#TOP 7

CARMOCAR Fuel Filter Water Separator for Marine Outboard Motor Mercury

WS-Z136
S3213 Assembly
CARMOCAR Fuel Filter Water Separator for Marine Outboard Motor Mercury Cover
CARMOCAR Fuel Filter Water Separator replacement for Marine Outboard Motor Mercury with 3/8" Barb x 1/4" NPT brass Fittings Replaces# S3213, S3214, 35-60494-1, S3213, 18-7932-1, 18-17928, 35-809097

The CARMOCAR Fuel Filter Water Separator is a high-quality replacement part for Marine Outboard Motor Mercury. Made of premium aluminum material, it offers long-lasting durability and reliability. The 3/8 NPT ports provide lower pressure drop rates, while the 10-micron filters are over 92% efficient at removing particles as small as 10 microns. The filter is a perfect fit for a variety of universal fuel applications and can trap the smallest particles and emulsified water from gasoline, reducing damage to your engine and other fuel delivery components.

What We Like
Constructed of premium aluminum material for long-lasting durability and reliability
10-micron filters are over 92% efficient at removing particles as small as 10 microns
3/8 NPT ports provide lower pressure drop rates
#TOP 8

CARMOCAR R12T Marine Fuel Separator

r12t fuel filter
R12T Assembly
CARMOCAR R12T Marine Fuel Separator Cover
CARMOCAR Marine Fuel Water Separator/Diesel Fuel Filter/Water Separator for R12T MARINE SPIN-ON HOUSING 120AT NPT ZG1/4-19 Includes 2 fittings,2 plugs

The CARMOCAR R12T Separator is designed for easy installation and maintenance. Its spin-on design allows you to quickly replace the filter, saving you time and effort. The clear nylon bowl lets you monitor fuel quality visually, ensuring you always use clean fuel. With a self-venting drain, you can easily remove unwanted water and debris without disassembling the unit. This feature not only simplifies maintenance but also optimizes engine performance by ensuring water-free fuel flows through your system.

What We Like
Easy filter replacement
Clear fuel quality visibility
Self-venting drain feature
Optimizes engine performance
#TOP 9

WIX Filters - 33405 Heavy Duty Fuel Water Separator

Wix
33405
WIX Filters - 33405 Heavy Duty Fuel Water Separator Cover
WIX Filters - 33405 Heavy Duty Spin On Fuel Water Separator, Pack of 1

The WIX Filters - 33405 Heavy Duty Spin On Fuel Water Separator is a reliable and durable filter that features a pleated paper filter and a mesh support screening. It is designed to provide increased dirt and water removal, which makes it an ideal supplement filter. Its drain plug allows for easy draining of excess water from the filter. It is also very easy to install and maintain.

What We Like
Easy to install and maintain
Provides increased dirt and water removal
Reliable and durable
#TOP 10

K&N Air Oil Separator for Ford F150 & Raptor

K&N
81-0800
Standard
K&N Air Oil Separator for Ford F150 & Raptor Cover
K&N Air Oil Separator compatible with 2011-2023 Ford F150 & 2017-2023 Ford F150 Raptor | Catch Can, Efficient Blowby Protection, 81-0800

The K&N Oil Catch Can is designed to protect your Ford F150 or Raptor engine from harmful oil contamination, helping to keep your engine clean and running smoothly. By capturing blowby gases, it prevents power loss and reduces the risk of engine knocking, which can improve your vehicle’s performance. This device also helps stop oil and dirt buildup inside your intake system, ensuring better engine efficiency. Plus, you can install it yourself in about 30 minutes, making it a convenient upgrade that doesn’t require a lot of time or effort.

What We Like
Effective blowby protection
Prevents power loss
Reduces intake contamination
Quick 30-minute installation
Buying Guide Image

Frequently Asked Questions (FAQs)

1. What function do fuel and water separators perform?

Fuel and water separators serve as an additional protection for your vehicle's fuel system. They filter out water and particulates from the fuel before it reaches the fuel filter, ensuring that only clean fuel flows to the engine. This helps prevent water contamination and potential damage to the engine.

2. Does fuel water separator work?

Yes, a fuel water separator is an essential component of a boat's fuel system. It effectively separates water and impurities from the fuel, ensuring smooth and efficient engine operation. It also helps to extend the life of the engine by preventing corrosion and damage caused by water and debris.

3. What happens if you don't change your fuel water separator?

If you fail to change or maintain your fuel water separator, water and other pollutants can mix with the fuel injector, potentially causing damage to the engine. Additionally, the check engine light may illuminate as an indication of a problem with the fuel water separator.

4. How often do you drain a fuel water separator?

It is recommended to drain water from the fuel water separator whenever the warning light illuminates or a message appears on the information display, indicating the need to drain the water separator. Typically, this occurs when approximately 6.76 fl oz (200 ml) of water has accumulated in the module assembly.

5. What are the disadvantages of oil water separator?

One disadvantage of an oil/water separator is that it only works effectively for oil-like substances that are water-insoluble or have a density similar to that of water. It may not function properly for oil in water emulsions, where the oil and water are thoroughly mixed. In such cases, alternative methods may be needed to separate the oil from the water.

Editor's Notes

During our fuel & water separator research, we found 24 fuel & water separator products and shortlisted 10 quality products. We collected and analyzed 37,191 customer reviews through our big data system to write the fuel & water separators list. We found that most customers choose fuel & water separators with an average price of $24.41.

The fuel & water separators are available for purchase. We have researched hundreds of brands and picked the top brands of fuel & water separators, including EVIL ENERGY, CAT, Wix, CARMOCAR, K&N. The seller of top 1 product has received honest feedback from 2,064 consumers with an average rating of 4.9.

Written by
Robert Reyes Avatar

Robert Reyes is a dedicated writer from San Francisco with a bachelor of degree in mechanics and a bachelor of degree in marketing. He focuses on making some complicated topics simple and enjoys explaining complex and technical things in an easy-to-understand way.