fuel line vent cutoff valve to diminish ethanol separation

[UncleWillie]

I love these discussions. :joyous: And the additive sellers hate to have their claims dashed with real facts instead of their shaky claims.

+1

I would be more than happy to see that the "Stabilizers" did anything measurable at all. Even slightly!
I can't find a single experiment to demonstrate anything.

Extensive research shows that the fuel industry tests motor fuel for "Gum" in a device they most appropriately call a "Bomb".

They partially fill a heavy container with the gasoline under test and and then purge and fill the remaining space with pure Oxygen pressurized to 100psi.
The container is sealed and heated to a temperature in the low 200F range for a couple of hours. (Don't try this at home!)
This simulates Months to Years of fuel aging in just a couple of hours.
The aged fuel is then pressure sprayed into a container preheated to the 300F range and the residue remaining in the container is measured as the "Gum" content.

I have found that I could crudely duplicate the deterioration by placing an open jar of fuel in the summer sun for about a week.
About half of it will evaporate, the rest will turn a noticeable Amber Color, and Fail my "Does it form a 'Head' when Shaken" Test.

This summer I prepared a jar of straight E-10, another containing Marine Stabil, and a third with 50:1 TCW-3 Marine Oil.
Each were given the "Head" test every day until they Failed.
All three failed on the same day. The Stabilized Fuel deteriorated just the same as the untreated fuel. Go Figure!
None accumulated any water from the exposure to the atmospheric water vapor.

Another experiment compared Treated fuel to Untreated fuel by adding add small, carefully measured, increments of water to each container.
All samples started to phase separate at the same concentrations. No measurable difference were found.

If anyone knows a test that will demonstrate ANY difference between treated and untreated fuel, I would love to hear about it.

 

[JimS123]

I don't personally have a "test", but I'm sure that someone associated with the petroleum industry does.

My first outboard was a 1955 Merc. The owner's manual said to stabilize the gas. Subsequent Evinrudes and their manuals said the same thing, and even listed an OMC recommended product. But, what did i know. I was just a teenager so i followed the directions. Have faithfully used gas stabilizer for 50 years. When I first heard of StaBil years ago, i switched to that. Have not had a gas related problem in 50 years...until this Fall.

Last Summer my Dad passed and i inherited his garden tiller. I used it and in my haste and laziness i stored it. I thought the tank was empty. A year later it wouldn't run. Fresh gas was all it needed. Year old unstabilized gas was unusable. My neighbor had not used his boat for 2 1/2 years and his stabilized gas ran fine.

BTW, I enjoyed the comment about we all know ethanol gas sucks water out of the air. Certainly, I didn't know that until i read the urban legend web site.....LOL.

 

[ondarvr]

Since 1965 I have never stabilized any fuel, so far no issues, I don't keep gas around for years on end though. All this means is that those that use stabilizer and those that don't have about the same results. I'm sure they do help, but it seems to be a solution to a problem I don't have. (been using E-10 for the last 20+ years)

I did purchase a couple bottles of Sta-Bil about 8 years ago, kept forgetting to use them, the shelf life ran out before I got around to it so I threw them away. I didn't have any fuel issues in those 8 years so I guess I didn't need them.

The test will be on an old Chevy PU I have, it's been sitting indoors for the last 7-8 years (maybe more) and I plan on selling it soon, I had put some Seafoam in it shortly before I stopped using it. It will be interesting to see what happens when I try to start it.

 

[Timeking]

Well, glad I posted. Dumb idea I had. I especially appreciate the 100% humidity calculation by Uncle Willie. Thanks.
EPA at http://epa.gov/oms/regs/fuels/rfg/waterphs.pdf says:
"In order for enough water to condense from the air to cause gasoline-water phase separation, however, there must be approximately 200 gallons of air per gallon of fuel over this temperature drop (100 to 40 degrees). Since oxygenated fuels can hold even more water than conventional gasoline, it is even more unlikely that enough water will condense from the air to cause gasoline-water phase separation."

As to those who suggested a fuel-water separator, uh, that won't work ... if your E-10 suffers phase separation, the alcohol will go right through the filter and damage the engine. That is a different problem than water in the tank, which the filter WILL catch.

I called my mechanic shop, and asked if phase separation and they said it was common.

 

[UncleWillie]

Phase separated Water/Alcohol acts just like water and will sit in the bottom of your tank, or the bottom of your Fuel Water Separating Filter, just as if it were Water.
If your tank isn't full, adding more E-10 to the mix brings in more Ethanol and if will place some, or all, of the phase separated fuel back into suspension.
It is an urban myth, that once it separates it can not be used; just add more fuel, or a bottle of "Heet".