Gone Fishin' : As the saying goes, water and gas do not mix
By Nelson Sigelman
Published: September 3, 2009
Not too long ago I had returned to the boat launch in Tashmoo after a morning of not very successful fishing. Jeff Canha was pulling up to the dock in his dory.
"You're lucky," Jeff said. At first, I did not understand what Jeff was talking about. He could not have looked in my fish cooler, I thought.
Tony Canha, 13, of Vineyard Haven holds up a yellowfin tuna he caught out fishing with his father, Jeff. On the same trip, Tony caught a 16-pound mahimahi and a 47-pound wahoo. The fish currently hold the top spots in the Massachusetts Saltwater Fishing Derby. Photo by Jeff CanhaBut Jeff, a charter captain and skilled marine mechanic, was referring to my old 30-horsepower Evinrude outboard engine. Apparently the simplicity of my two-stroke was its saving grace.
Jeff said every week he received calls from boat owners with engine problems. Fuel containing ethanol is the principal cause.
I did not get a chance to talk to Jeff that day, but caught up to him later. He was cleaning a catch of yellowfin tuna aboard his 35-foot diesel-powered H and H Marine boat.
"You have a simple system," said Jeff, explaining his earlier comment to me.
In recent years marine engines have become as complicated and sophisticated as automobile engines, he said. That is both good and bad. The engines are far more fuel-efficient but they are also not easy to repair and far more likely to be affected by variations in gasoline.
There is another important distinction. Most people drive their cars every day. As a result, fuel does not sit in the tank for weeks at a time.
Why does all this matter? Well, the push to lessen America's reliance on oil from the Middle East resulted in the addition of ethanol to the gasoline supply.
Ethanol is made from corn. That was good for corn growers but not so good for world food prices and owners of old boats.
Ethanol is an excellent solvent. The new gas began dissolving resin and other gunk in old fuel tanks. It also began to dissolve certain types of fiberglass fuel tanks in older boats.
Eventually, the gas tank problem got sorted out. Think of it as an early version of the recovery plan, but for marine mechanics.
The lingering issue and the one Jeff was referring to is related to another property of ethanol. According to a National Marine Manufacturers Association (NMMA) press release, "because ethanol absorbs water, higher amounts of ethanol in fuel equate to higher amounts of water in fuel tanks. This, naturally, causes corrosion, which itself creates particulate matter that then clogs fuel filters, fuel systems, and damages engine components. The harsh marine environments in which boats operate accelerate this rate of corrosion.
"Features common to boats further exacerbate corrosion, such as copper from brass fittings. Mid-grade ethanol also causes galvanic corrosion in aluminum tanks since the presence of ethanol and water will conduct electricity. Fuel tank corrosion can perforate aluminum fuel tanks, producing leaks that may pollute marine environments."
If a boat sits unused for too long, the ethanol can become saturated, separate from the gasoline, and form two solutions. The experts call this phenomenon "phase separation."
Back to my conversation with Jeff, who also teaches auto mechanics at the Martha's Vineyard Regional High School. Automobile gas tanks are designed around a closed system. Boat gas tanks are vented which allows moisture to enter the tank and condensation to develop.
"That is where the problem lies," Jeff said.
Gas sitting in a boat that is unused for a period of time begins to absorb moisture. At a certain point it separates. One step boat owners can take to avoid problems is to keep fuel fresh. Fuel water separators, frequent filter changes and fuel additives may also help.
But there is more good news. The Environmental Protection Agency (EPA) is considering a request by Growth Energy, a pro-ethanol lobby, to allow the ethanol blended with gasoline to be increased to 15 percent. EPA has until December 1, 2009, to grant or deny Growth Energy's waiver petition.
Fish reports
Speaking of Jeff Canha, on Tuesday he returned to the dock from about 30 miles south of the Vineyard. Jeff said he caught bluefin tuna in the 40-pound range and false albacore. He said the albies were breaking everywhere.
That is good news for Island fishermen with more limited striking distance. A distance of 30 miles is a short flick of the tail for a school of albies.
Last Friday I sat off State Beach waiting for a crack at one of several schools of albies. There were about 20 other boats.
For the most part, it looked as if folks were trying to be respectful. Boats maneuvered around breaking fish instead of plowing right up to them, cutting off other fishermen in the process.
I cast a Deadly Dick into fish several times without any luck. When spinning tackle proved fruitless I decided to trade distance for realism and picked up my nine-weight fly rod.
As other boats chased a breaking school I would attempt to guess where the fish would turn up next and get in front of them. It was a fairly effective strategy in the sense that I got about three good shots at breaking fish.
I watched two different albies come right up to the fly and veer off at the last second. I think what happened is that by the time the albies focused in on the fly I had stripped in too much line and the fly was approaching the boat.
That and the sight of me likely spooked the albies.
Still, it was nice to be on the water following a trip the previous weekend to Vermont.
My wife and I spent some time in Brattleboro. I think I was the only guy over 50 without a ponytail.
The 64th annual Martha's Vineyard Striped Bass and Bluefish Derby begins at 12:01 am Sunday, Sept. 13. Next week I will write more about the changes fishermen can anticipate.
This is the week to spool up reels with fresh line and change rusty hooks. It would be unfortunate to lose a Derby-winning fish because you decided to save money on the cost of fresh line.
