posted 09-19-2010 01:10 AM ET (US)        

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I filled up my 4Runner at a Mobil station in San Diego today and got to thinking: in California what percentage of the fuel is ethanol? I asked the attendant and she checked the delivery paperwork from that day; [the percentage of the fuel that was ethanol] was listed at 10-percent. I know California lists [the percentage of the fuel that contains ethanol as] 10-percent so that when [the actual percentage of ethanol in the fuel in California] gets [to 10-percent], [it] won't [be necessary to change] any literature. I suspect we are already at 10-percent now, anyway.

I may start filling my boat up in Tijuana, Mexico. It's less than 30 miles away from downtown San Diego. [Fuel in Tijuana is] cheaper and I believe it's ethanol-free. Is [fuel with a blend of ethanol and gasoline] only a [concern] with fiberglass fuel tanks? Or, is [blended gasoline and ethanol fuel] gunking up my engine, as well? Am I paranoid? Is [visiting Mexico only for the purchase of fuel without ethanol] worth the hassle? When is the border crossing time predictably shortest? For most of the country this may not be applicable. These are questions about ethanol in our gas.

posted 09-19-2010 08:51 AM ET (US)            

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To determine the percentage of ethanol in your local gasoline you could test it yourself. I described a method in an article published in the REFERENCE section a few years ago. See

Ethanol Fuel Testing
Determining ethanol content in blended gasoline fuels
http://continuouswave.com/whaler/reference/ethanolTest.html

Many marine retailers of gasoline sell fuel without ethanol. If you want pure gasoline, check with a local fuel distributor and see if there are any retailers in your area selling it. Travel to a foreign country to purchase fuel seems like an extreme solution.

posted 09-19-2010 09:16 PM ET (US)            

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Jim -

Once ethanol mixed fuel "phase separates", can it be reconstituted by movement?

Example, if someone had a large amount of fuel on board a vessel, and didn't move it from it's slip more then a few times during the season.

D

posted 09-19-2010 09:28 PM ET (US)            

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The virtue of ethanol and gasoline blended fuel is that it can hold more water in suspension than pure gasoline, however, once the water content reaches saturation, the water separates from the fuel and usually takes the ethanol into solution with it. This leaves the gasoline without its oxygenate, and with an octane that is too low.

Some newer products claim to be able to help restore phase separated blended fuels.

Agitation seems like it can temporarily create an emulsion of the phase separated ethanol and water, but I don't think it will provide a permanent solution.

posted 09-19-2010 10:39 PM ET (US)            

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Here is some info on the problems in Tiajuana.

[htm]http://www.independent.co.uk/news/world/americas/tijuana-caught-in-the-cocaine-crossfire-1647371.html[htm/]

posted 09-20-2010 03:54 PM ET (US)            

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I am well aware of the issues in Mexico and Tijuana for that matter. As a San Diego native, I spent many weeks/months of my youth in Tijuana, surfing in San Miguel, Rosarito, San Felipe etc. It's sad how the place has gone bad in so many ways.

Most people there are good people, albeit poor. Occasional rip off etc. I still go south of the border on occasion, once you get past the border and into Baja I find fewer problems.

If i were to pick up gas there it would be in jerry cans most likely or perhaps a few 6 gallon tanks I have from over the years. I haven't taken my boat by land into Mexico in years, although cross in the water all the time ie Coronado Islands, 9 mile bank etc.

posted 09-30-2010 08:10 PM ET (US)            

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I live in Mexico 9 months a year. Gas there has no ethanol. It is 87 octane. Much of it is refined in the U.S and in any case is comparable quality. It does have fewer additives and slightly more dirt. It ran my [Mercury EFI FOURSTROKE] fine for four years and 1,300-hours.

No one gives a [care] in Mexico if you carry gas cans. The problem is getting the fuel in cans back through U.S. customs. It falls into the category of imported merchandise and there is a dollar limit on the amount that can be imported. Our Customs and Border Protection people are touchy and might feel too much gasoline is a threat.

Mexican insurance is necessary for any vehicle including a boat trailer in Mexico. That would probably make it uneconomic to fuel your boat there unless you planned to use the boat in Ensenada, Guerra Negro or points south.

posted 09-30-2010 08:45 PM ET (US)            

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Thanks for the information on Mexico, their fuel, and their insurance regulations. These days the notion that you could travel abroad to purchase fuel and import it back to the United States as a way to save money is probably no longer reasonable. Many years ago we used to travel to Canada from Detroit to purchase fuel in Windsor. The border crossing was very casual, the currency exchange was very favorable, and the price differential in fuel sufficient to make it somewhat advantageous.

With border crossing more tightly controlled now, the thought of travel to Canada or Mexico just to buy gasoline seems farfetched, unless there were dramatic advantages to be obtained in price or fuel quality. In the case of Canada, it is out of the question as their fuel prices are always higher than in the U.S. In the case of Mexico I suppose fuel prices are lower in Mexico, but the hassle of the border crossing seems to limit the potential upside to this adventure.