Steve DíAntonio on Fuel Polishing Installation
Iíve found that the majority of fuel polishing systems I encounter here in the boat yard (other than the ones we install
), are not plumbed in such a way as to maximize their efficiency. Thatís a fancy way of saying they are often strangled by undersized plumbing
or they are incorrectly plumbed to the tanks
For a fuel polishing system to work as well as possible, two criteria must be met. First, the plumbing
should be entirely independent from any existing engine or generator
fuel supply or return plumbing. Why? Existing plumbing fittings are often too small to handle polishing system volume and the polishing system plumbing may compromise the engine or genís fuel supply or impede its return (this can cause injector pumps to malfunction). Second, the polishing systemís supply and return plumbing inlet and outlets should both be located close to the bottom of the tank. This ensures that the debris and water
are being picked up by the polisher and it sets up a current
that will scour the bottom of the tank, picking up loose debris. Additionally, the problem with returning fuel to the top of the tank, for both polishing systems and engines, is that the splashing created by this practice aerates the fuel. Air entrained within the fuel, if it should make it to the injection system, will cause erratic operation and it hastens the fuelís oxidation, which essentially makes it age more quickly.
Given the choice, I prefer to install fittings at or near the top of the tank and then utilize drop tubes the draw and return fuel from the tankís bottom. This minimizes the possibility of leaks
and still ensures efficient fuel polishing.
Steve C. DíAntonio