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A Common Mistake

This is a hot button topic so don't get too worked up over it!

Gas prices continue to rise in this world. We're all looking to save a few bucks as well. You've probably considered, a time or two, just grabbing the ole jerry cans from the shed and topping off the boat with the same trusty 87 octane fuel that your car gets. You're thinking, "why not?" You might save yourself a couple bucks on the gallon right now. Every little bit helps, right? WRONG!

We're going to give you some stories and advice as a marina that is no longer in the business of selling gas. So do not think we are just here to push a more expensive fuel to make money. Mind you, we never made money on our gas sales anyway.

I'm going to start by going through the adverse effects of using ethanol-based fuels in your marine engine.

1) Ethanol fuel has a shelf-life of approximately 90 days. Engines are getting more and more fuel efficient, and boats are getting larger fuel tanks than ever before. We have many customers who only use one tank every season. Obviously, this poses a problem right away. As soon as that gas goes bad, the hygroscopic effects of ethanol kick in...which brings me to my next point.

2) Ethanol is hygroscopic. For those who don't know what that means, it's the opposite of hydrophobic. Ethanol attracts water. It's common practice for condensation to occur in your fuel tank, especially in the spring and fall seasons. Ethanol will absorb that water. As much as we'd love an engine that runs on water, we're not quite there yet. Therefore, WATER IN GAS IS BAD!

3) Ethanol can cause fuel lines, fuel filters, and fuel injection/carburetion components to break down at a faster rate. Don't believe it? Spray ether on a piece of plastic or rubber. Ether and ethanol are extremely similar in structure. They will cause plastic and rubber to deteriorate. I promise you, a lot of your marine engine's fuel system is plastic and rubber.

"But TJ my owner's manual says I can use up to 10% ethanol fuel in my boat!" Ok. You got me. Yes, that might be true. However, when you go to the gas pumps do you test the fuel for ethanol content before you fill your boat up with it? Of course not. That's too much work. Are you going to just trust that sticker on the pump? Even if it is only 10% ethanol, let's refer back to the shelf-life of ethanol fuel.