A fuel water separator is a vital element for any common rail diesel vehicle. A fuel water separator prevents blockages and abrasions between the delivery pump and fuel injectors and is critical to the efficient running your diesel vehicle. Ryco's Fuel Water Separators remove impurities before they reach the primary filters, improving the longevity of your vehicle. Ryco Fuel Water Separators: hinder water and other contaminants from entering the fuel filter. They deter bacteria and algae growth