Related article

Hi George,

Looks like you have been busy. I have been researching filters and fuel issues, and thought I would copy a portion of the article I found recently, that cautions about leaving fuel in tanks, how the octane will lower during the season and cause driving problems, etc. It also can gel up filters.

Dave
















Fuel for Thought
Here are four ways to save a tankful.


By John Wooldridge
Published: January 2006
Yachting Magazine

It’s the middle of winter and you’ve finally boarded the yacht that you delivered to sunnier climes last fall. Business, family and the holidays have kept you away several months, but now you’re looking at two weeks of cruising through the Keys and maybe even a jump over to the Bahamas. The Gulf Stream is rough, but not so rough that you’ll stay at the dock. About an hour into your cruise, an engine suddenly shuts down. You limp into the nearest port and, after careful consideration by an engine specialist, learn that your problem is fuel related. You feel a little queasy because the fuel problem could easily have shut down both engines. And from that moment forward, you decide that fuel management will become just as important as regular engine service.
Fuel management isn’t just a matter of safety. With the wildly fluctuating prices of fuels likely to remain a reality in the coming seasons, anything you can do to increase the efficiency of your engines, as well as the reliability of the fuel supplied to your engines, needs to be carefully considered.
The two biggest ways to ruin a tank of fuel—on a diesel or gasoline powered yacht—are water contamination and long-term storage. When you keep fuel stored and unused for more than three months, the higher aromatics that give you the octane and cetane ratings begin to evaporate. Gasoline that was rated 87 octane at the pump can become a barely usuable 80 octane by the end of a season.
Diesel starts separating and a substance akin to crude oil settles to the bottom of the tank. Gasoline breaks down into resins, varnishes and acids. Furthermore, on a rough day as the fuel supply is agitated, those contaminants will be lifted into the main body of fuel. If they are pulled into the fuel filters and pump, engine failure will likely occur.
To help ensure that you never have that queasy feeling again, try these strategies to keep your fuel clean, starting with filters and additives and progressing to fuel polishing equipment.
1. FILTER
The best-known name in fuel filtration for recreational boats is Racor, a Parker Hannefin company. Racor makes a wide variety of spin-on filters with clear contaminant collection bowls and drain valves for gas and diesel engines. Its duplex Turbine Series models are good for high-capacity water separation and fuel filtration because they allow the owner to throw a lever and switch to a fresh filter while the engine is running, postponing a shutdown and filter change at sea.
2. STABILIZE
Additive manufacturers are almost as numerous as over-the-counter pain relievers, but some specialize in recreational marine needs and remain in the forefront of fuel technology. Star brite, manufacturers of storage stabilizers for automotive and marine fuels and other maintenance products, has recently introduced Star*Tron, an enzyme-based additive for gas or diesel fuels that solves a host of fuel-related problems.
“At the end of the boating season last year, we were getting fifty to sixty calls a day from boat owners in the Northeast and Midwest complaining about gummy, gooey substances clogging the surfaces of their fuel/water separators,” says Jeff Tieger, vice president of sales for Star brite. “It was gelling because of ethanol. Ethanol in alcohol-enhanced fuels acts as a coupler between hydrocarbons and water. When you have early or late-season temperature fluctuation in tanks, and fuel stays stored for long stretches of time, gelling takes place.”
3. SEPARATE
Even pure diesel fuel will pick up about 5 percent (that’s fairly high) water through distribution channels. Gasoline will pick up 1 to 2 percent, but alcohol will increase its levels to 7 or even 8 percent. Any container that holds fuel will have some humid air and will be a source for water. For this reason, water separators have been the chief line of defense for diesel engines.
“Star*Tron’s enzyme opens up the bonds that hold fuel molecules together, making them more receptive to oxygen at combustion, giving something closer to complete combustion,” explains Tieger. “Enzymes are biocatalysts, they don’t get consumed in the reaction, but they will initiate or control the rate of the reaction. The result is more fuel economy, less harmful emissions—down 90 percent.”