Fuel Additives

As much as I dislike ethanol in our fuel it seems that it is here for a while so we may as well learn to live with it as well as we can. To minimize the adverse affects of the ethanol many companies have developed fuel additives to protect the fuel. They all claim to be the best and the answer to our needs but I want to know from personal experience which ones work and which ones don't, and maybe even which is the best. To accomplish that goal I started a hands on, side by side test of various brand name additives in known ethanol laced gasoline. That test was started on 10/1/10, so it's been one year to date that the test has been running. The results were interesting.

First step was to verify that I had an ethanol/gasoline mix. I bought a gallon at the local Hess station and poured a small quantity in a glass jar. With an eye dropper I added a few drops of water. The drops fell to the bottom of the jar as beads but as I stirred the fuel the water suspended in the fuel and did not settle out. I repeated the procedure several times before I reached saturation where it would no longer suspend, and then I witnessed phase separation where the ethanol/water mix fell to the bottom of the jar. Sure enough, the quantity of mixed fluid on the bottom of the jar was quite a bit more than the quantity of water I'd added to the fuel assuring me that I had ethanol in the fuel.

Step two: I took seven equal sized jars and added an equal amount of fuel in each jar. Then I took six brands of fuel treatment and added the recommended quantity of each in the fuel, leaving one jar with pure gasoline/ethanol mix. The jars were vented and left in an open air garage as if stored in a vented container, or the fuel tank of the typical boat. After one year I have what I consider to be valuable results.

Brands tested:

Stabil
Stabil Marine
Startron
Valvtect
CRC Phase 4
BRP 2+4 for Ethanol fuel

Symptoms tested for and noted:

Evaporation. As fuel sits it slowly evaporates leaving a sticky residue which can clog carburetors and injectors. If the additive can prevent this you'll save hundreds of dollars in rebuilds and clean up. Evaporation also robs the fuel of needed hydrocarbons and such degrading the fuel of BTU's and octane. It's obviously better if we can prevent this and have a use able fuel after a reasonable storage time. Based on past experience with stored fuel I gave the evaporation protection the highest importance.

Moisture absorption protection. By now most of us know that ethanol fuel is very susceptible to water absorption which creates all sorts of havoc in the fuel systems of any gasoline engine. If we can stop or slow that process the additive is wonderful stuff.

Inhibit organic growth. Most do not know of this phenomenon but when water is absorbed into ethanol the result is an organic based mix quite hospitable to organic growth such as mold and mildew. If you've ever siphoned off the mix from the bottom of a fuel tank after phase separation has taken place and noticed the little flakes floating around in it, that's what I'm talking about here. The best way to slow this is obviously to slow the water absorption but it's important to slow the growth of the organics as well since moisture absorption to some extent is inevitable.

This covers the methods used and the test criteria, now for the results.

Startron came in first with the best protection against evaporation, crystal clarity of the mix after one year suggesting no organic growth, and no phase separation.

Valvtect scored a strong second with only minimal clouding of the mix, no separation, and evaporation protection equal to Startron.

Stabil Marine with excellent protection against evaporation, some clouding, and no separation.

The others were a mixed bag. None of them showed any sign of phase separation. Some were extremely cloudy. One offered no better protection against evaporation than the straight gasoline. No need to name names here since my mission is accomplished. So many folks ask what I would recommend and the three mentioned here get that nod. I'll never store over a year and all of them did a great job up to that point.