Originally Posted by johnnydmetal
Dino
From what I've read and been told when you do a ethanol conversion you want to eliminate all aluminum because it agressively attacks it. Steel begins to rust as alcohol tends to absorb water from the air. That causes sediment in the tank which can damage the carb or injector system and later destroy the tank. Poly tanks or Stainless are the best at resisting the alcohol. Actualy the steel tanks that resist alcohol have thick zink plate inside and will resist the corosion for a time.
I think you need to read a little harder, as the water concentration problem would be if the system were left open to the air, but with most modern closed sytems to keep emissions down, that is no longer an issue. Also, if you have that kind of cancentration, you will have engine troubles as well.
http://en.wikipedia.org/wiki/E-85
In addition to corrosion, there is also a risk of increased engine wear for non-FFV engines that are not specifically designed for operation on high levels (i.e., for greater than 10%) of ethanol. The risk primarily comes in the rare event that the E85 fuel ever becomes contaminated with water. For water levels below approximately 0.5% to 1.0% contained in the ethanol, no phase separation of gasoline and ethanol occurs. For contamination with 1% or more water in the ethanol, phase separation occurs, and the ethanol and water mixture will separate from the gasoline. This can be simply observed by pouring a mixture of suspected water-contaminated E85 fuel in a clear glass tube, waiting roughly 30 minutes for the separation to occur (if it does), and then inspecting the sample. If there is water contamination of above 1% water in the ethanol, a clear separation of alcohol (with water) and gasoline will be clearly visible, with the colored gasoline floating above the clear alcohol and water mixture.
For a badly-contaminated amount of water in the ethanol and water mixture that separates from the gasoline (i.e., approximately 11% water, 89% ethanol, equivalent to 178 proof alcohol), considerable engine wear will occur, especially during times while the engine is heating up to normal operating temperatures, as for example just after starting the engine, when low temperature partial combustion of the water-contaminated ethanol mixture is taking place. This wear, caused by water-contaminated E85, is the result of the combustion process of ethanol, water, and gasoline producing considerable amounts of formic acid (HCOOH, also known as methanoic acid, and sometimes written as CH2O2).
In addition to the production of formic acid occurring for water-contaminated E85, smaller amounts of acetaldehyde (CH3CHO) and acetic acid (C2H4O2) are also formed for water-contaminated ethanol combustion. Nonetheless, it is the formic acid that is responsible for the majority of the rapid increase in engine wear.
Engines specifically designed for FFVs employ soft nitride coatings on their internal metal parts to provide formic acid wear resistance in the event of water contamination of E85 fuel. Also, the use of lubricant oil (motor oil) containing an acid neutralizer is necessary to prevent the damage of oil-lubricated engine parts in the event of water contamination of fuel. Such lubricant oil is required by at least one manufacturer of FFVs even to this day (Chrysler).
For non-FFVs burning E85 in greater than 23.5% E85 mixtures (20% ethanol), the remedy for accidentally getting a tank of water-contaminated E85 (or gasoline) while preventing excessive engine wear is to change the motor oil as soon as possible after either burning the fuel and replacing it with non-contaminated fuel, or after immediately draining and replacing the water-contaminated fuel. The risk of burning slightly water-contaminated fuel with low percentages of water (less than 1%) on a long commute is minimal; after all, it is the low temperature combustion of water contaminated ethanol and gasoline that causes the bulk of the formic acid to form; burning a slightly-contaminated mix of water (less than 1%) and ethanol quickly, in one long commute, will not likely cause any appreciable engine wear past the first 15 miles of driving, especially once the engine warms up and high temperature combustion occurs exclusively.
I'm basicly looking for alternatives to Stainless that are more easily repaired since a puncture on long haul would leave you stranded till you located a shop that could weld it shut.
Ever heard of JB weld?
Copper on the other hand would make it possible to solder the hole in a few minutes with a little paste, solder, and either a hot iron or a torch propane or butane. A small butane torch would fit in most glove boxes.
BAAAAD idea, as heat or open flame around a flammable substance is a recipe for disaster, that is why noone welds on gas tanks... Ethanol burns clear, so it would be harder to tell if it is even burning until it is too late, and you are working on a leak to seal? The only way you could do that is remove the tank, fill with water, then solder, not exactly an easy fix in my book.