Also, “a clean, smooth bottom is a real efficiency enhancer,” says product manager Karl Sandstrom, a 21-year Evinrude veteran. If you keep your boat at a slip or mooring, use a quality bottom paint. Traditional “hard” paints are effective anti-foulants, but they create a cratered surface after a few years of built-up coats. If your boat’s bottom looks like the Sea of Tranquility, break out a scraper, or hire a bead blaster to remove that old cratered paint. Efficiency mavens select ablative paints, such as Interlux Micron or Pettit Hydrocoat. These wear away, leaving a smooth surface. If your boat has sat idle for a while, it pays to hire a diver to scrub the bottom or to don a mask and fins and do it yourself.
Of course, keeping an engine in top shape counts toward the economy total. Adhere to the maintenance schedule in the owner’s manual. Send the prop out for reconditioning if you bend a blade. (Or learn to coax dings back to normal with file, mallet and the judicious application of double-wrenching.) The recipe for maximized efficiency is like stew, rich with many ingredients that add up to something good. Apply the techniques we tested, and watch your fuel gauge move slower and slower and slower.
Our guinea pig was a 25-foot Bluewater 2550 center console, powered by twin 200 Evinrude E-TEC outboards. Our battery of tests were run in salt water, measuring fuel burn using Evinrude I-Command NMEA 2000 instruments reading directly from the engines’ electronic control modules. Speeds were recorded from a Lowrance LCX-26 GPS. All runs were done in two directions, to negate the effects of wind and current.
Dollars and Cents
Tallying all gains and losses from the testing done with our Evinrude-powered Bluewater, and extrapolating that data, resulted in these eye-opening, albeit idealized, results based on running 100 hours at 30 mph.
Back Off, Burn Less
Simple but true: Back off the throttle to burn less fuel. Naturally we don’t expect you to troll everywhere, but unless you’re in a tournament, are racing to make a bridge opening or have that momentary need for speed that afflicts us all, slow down to save fuel without costing any real time. Check out the 15-mile run numbers from our Bluewater test boat (shown above).
Do You Know It Takes...
2 gallons of crude oil to make 1 gallon of gasoline
26 pounds of corn to make 1 gallon of ethanol
1/2 pound of fuel to make 1 horsepower per hour
1 gallon of gasoline = 6 pounds
1 gallon of diesel = 7 pounds