How A Water Separator Fuel Filter Works

Author: Stuart Buckingham   Date Posted:21 November 2018 

Blog How A Water Separating Fuel Filter Works

Bad fuel can quickly cause problems for outboard engines by clogging injectors, gumming up carburettor jets or causing all sorts of running problems that can result in a shortened outboard life and hefty repair bills.


Water and impurities can enter a boats fuel tank in a number of ways, such as:

- incorrectly located fuel tank breathers and tank fillers,

- condensation forming in the fuel tank or

- by purchasing contaminated fuel from a petrol station.


Breathers and fillers can be easily replaced or relocated, however, there is little you can do about condensation forming inside your fuel tank or stopping contaminated fuel from a third party. But, the solution to avoid these is to install a water separating fuel filter assembly and here's why.


A water separating fuel filter is designed to catch the impurities or water before they reach your engine. The principle behind this filtration system is surprisingly simple; the top of the filter consists of a paper element and the bottom of the filter is a holding tank or bowl. Since water is heavier than petrol, water sinks to the bottom of the filter where it stays until it is emptied. In my opinion, the best version of water separators are the clear bowl type. They allow you to see if water is gathering in the bottom of the system and then drain it out with the integrated tap.


For routine servicing, the filter cartridge should be replaced and the existing bowl re-attached. Installation of a water separating fuel system is simple and you don't need a lot of mechanical knowledge to fit one. It should really take between 15-30 minutes, but may take longer if the area you're fitting it to is difficult to access or requires modification, and set you back about $50-$85 depending on the brand and setup you need.


It's good piece of mind knowing you're protecting your outboard in the event of water or other contaminants finding their way into your fuel. Installing one will be one of the smartest decisions you will make in caring for your outboard.


To shop our range of water separating fuel filters, click here.

Leave a comment

Comments have to be approved before showing up