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Magnetizing Your Diesel Fuel

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Near the end of the 2005 boating season, Richard Thiel, PMY's editor in chief, was in trouble. Just a few hours before he was about to fly to Italy, fuel problems had strangled his boat Ava T. in the middle of Long Island Sound. Since the fear of missing an expense-account junket to Europe haunts every member of the boating press, Thiel, an expert mechanic before moving to an editor's desk, changed the clogged fuel filters and bled the engine with lightning speed, managing to get home just in time to catch his flight. He vowed not to relive the experience and before launching for the 2006 season called the folks at Algae-X.


Who knew that was in there? The coalescer extracted this gunk from only one fuel tank; there's enogh in the cup to stop an engine in its tracks.

Algae-X International builds compact fuel-conditioning systems that can be installed on any diesel engine; you'll find them not only on boats, but on trucks, buses, cars, RVs, construction equipment, stationary gensets, and so forth. Unlike conventional fuel-polishing systems, which use ultra-fine filters to sieve out sludge, dirt, and assorted gunk, Algae-X technology rejuvenates the fuel. (Algae-X fuel conditioners don't replace filters and water separators, but work in association with them.) Many top boatbuilders and engine distributors, including Cummins MidSouth, are installing Algae-X fuel conditioners as standard equipment.

The problem Thiel faced is common nowadays, explains Bill O'Connell, president of Algae-X, thanks to changes in the petroleum refining process. When there was plenty of crude oil available, diesel, gasoline, and other lightweight oils were refined by distillation, which produced lovely, creamy, long-lasting diesel that looked almost good enough to drink. It was chemically stable and could be stored for years with no ill effects. Unfortunately, distillation converts only about half the crude oil into light fuels; the other half becomes heavy Bunker C oil (used aboard ships to fire boilers) and assorted petroleum products for manufacturing plastics, synthetic fabrics, cosmetics, asphalt, etc. But during World War II, when the need for fuel was acute, chemists developed a way to extract more light fuels and oils from the crude: Using a solid catalyst to "crack" the molecular bonds converted about 85 percent of the crude oil into fuel. After the war ended, "cat-cracking" became more prevalent, and for the past 25 or 30 years, most crude has been refined that way.

Unfortunately, O'Connell continues, cat-cracked diesel isn't as stable; over time the forcibly separated light hydrocarbon molecules reconnect to form heavy hydrocarbons and, eventually, sludge. Sludge is a conglomeration of paraffin and asphalt, but today most people just call it "algae." "That's why we called the company 'Algae-X,'" he explains.

This article originally appeared in the January 2007 issue of Power & Motoryacht magazine.