Going through the frustrating process of dealing with bad marine fuel? Be it diesel or gas, you’ll want to know how to start fresh and completely eliminate the problem. Bad fuels can come from water (condensation), debris (dirt or metal oxidation-rust), algae or varnish build-up as fuel ages.
The first signs of contamination can be seen in your fuel filter. Keeping the filter clean goes a long way to keeping your engine running right. I recommend an in-line fuel filter placed before the fuel pump. This will keep the pump from wearing out due to the contaminants. If you suspect water contamination, sound the tank for more water (it will be on the bottom of diesel tanks and can be measured by water-activated paste on a sounding stick). You may want to invest in a water-separation filter like a Racor filter if you have persistent condensation problems. Whatever the cause of the problem, a thorough flushing of the fuel tank, a change in filters, and the proper disposal of old bad fuel is the only way to get a fresh start.
Hopefully, we’ve come a long way since the days when we dumped old oil down the storm drain, poured old gas on the ground or, in my case, when we used waste oil to grease a marine railway instead of getting rid of it with less impact to our environment. I was the ops manager of a 100-year old boatyard undergoing a massive infrastructure makeover; eventually we transitioned to be a “small” producer of hazmat material, and there were proscribed ways of handling contaminated fuels. But first we had to get rid of the backlog of used oils, foul fuels, and contaminated bilge water found everywhere in various containers among the 14 buildings about to be demolished. Dealing with everything from hundreds of cans of old paint to waste oil and barrels of contaminated fuel helped me understand how to dispose of it all in the best way we presently know how.
This large quantity of bad fuels and oils led directly to our advice to individual owners on how to deal with their boats’ old materials:
- Don’t ever leave it by the dumpster. Go to the marina office for direction; they’d much rather deal with the fuel and oil through their systematic process than see it go in the trash or be spilled on the ground. In many cases they will advise you how to take it to a local recycling center, or will gladly take it themselves. Local recycling centers actually make money by recycling everything from oil to old batteries, and without much cost to you beyond the expense of an annual town sticker on your car.
- Don’t ever dump even small amounts of fuel or oil on the ground. You know why!
- Find someone with a waste-oil heater, but be careful: Transporting large quantities of old fuel or oil on our highways is restricted by law as to the mode of transport. Throwing barrels of fuel in the back of an open truck doesn’t cut it as a “safe mode” of transport, and is a fineable offense if you’re caught — which isn’t much reward if you’re trying to do the right thing. It may mean delivering the bad fuel to the waste oil heater in smaller quantities, a bit at a time.
- Consider fuel-polishing alternatives.