Make SURE you are buying non-ethanol gas CORRECTLY

[RJ Hamner 1,001]

I have been using the non corn squeezins gas for several years now

I add 2 oz of Lucas Upper Cylinder Lube to the 5 gallon can.

All the horses like it.

Never had a problem.  Unlike the run of the mill stuff.

[wh500special 2,076]

I don’t know how long ethanol enhanced gasoline has been widely used in my part of the Midwest, but it’s been at least my entire driving career of over 30 years.  As far back as high school (for me 1989-1993) I can remember that Caseys gas stations sold ethanol laced 89 octane for a lower price than their regular 87 octane straight gas.  The other stations didn’t mimic Casey’s pricing strategy (and Caseys gave up on it too), but the bulk of their fuel was also fortified with ethanol.  Few problems resulted.

 

One of the benefits of alcohol in gasoline is that it can capture some amount of water and pull it along harmlessly.  Used regularly and continuously, this means it grabs hold of any water in the tank and keeps it from accumulating.  In small amounts, the water passes through completely unnoticed.  Over the counter additives like Heet do the same thing to help dry out a gas tank that has a little bit of water in it.

 

But the alcohol/gas mixture can only hold a finite amount of water.

 

In the case where an older car had never been fueled with alcohol containing fuels – or in storage tanks where only gasoline had ever been held – there could be a significant amount of water sitting in the bottom of the tank.  In this water are the water-soluble contaminants and dirt that don’t dissolve in the organic portion of the mix.  When alcohol is introduced to these tanks it can make all of this contamination available for ingestion by the engine.

 

This phenomenon was in fact fairly common during the initial changeovers to alcohol blended fuels.  There’s a lot of time and expense involved in dumping out a tank completely so it wasn’t done in many cases unless a problem developed.  Once all the residual gunk and water was out of the tanks, this became less commonplace.  I didn’t search for corroborating evidence of this, so hopefully it exists.  It used to be in common discussion decades ago in my circles.

 

Additionally – and this was mentioned in the boating article Ed linked – straight gasoline and alcohol have different solvent properties.  This means that the stuff that ends up in the fuel distribution tanks, your portable gas can, your car’s fuel tank, your boat’s underfloor fuel tank, or the little tank and carburetor in your Wheel Horse can eventually accumulate some materials that aren’t dissolved by gasoline.  When alcohol is introduced, some of this stuff can reenter solution as the alcohol and/or water chews on it.  So jets can plug with debris that didn’t cause problems before and crud and schmutz can get into functional areas where they weren’t previously.  If you evaporate out the fuel due to sitting, this stuff can crust up in there and may defy dissolution by normal cleaners used in fuel systems.

 

Phase separation happens in both straight gas and in alcohol enhanced fuels.  Water and gasoline do not mix in appreciable quantities.  If you dump a cup of water in a gigantic fuel storage tank that is filled with straight gasoline, the water will fall to the bottom of the tank and sit there as discrete droplets or as a puddle.  It will probably extract some amount of water soluable compounds as it falls through the solution too.  Phase separation is therefore instantaneous and easily detectible in straight gas situations. 

 

Perhaps phase separation isn’t the right term in the above scenario.  I guess since they never mix and create a single phase that it’s technically different that what is considered when the water/alcohol mix drops out of the gasohol.

 

Mix 10% alcohol into the gasoline and now you have available a molecule that can hold onto water or dissolve into water in any proportion.  Water and alcohol are both polar molecules meaning that they have one end with a negative charge and one end with a positive charge.  So they have some similar properties, one of which is miscibility.  This was the “like dissolves like” lesson touched on in high school physical science classes.

 

The interesting part is that the alcohol molecule also has a substantial chunk of it that exhibits properties that are similar to things like gasoline.  These uncharged things are known as non-polar molecules.  This means that most alcohols also exhibit solubility in non-polar gasoline too.  They sort of walk the line between two worlds.

 

But there are solubility limits of most any solvent/solute combination.  Put too much sugar in your iced tea and eventually you’ll see a sludge of undissolved sugar sitting in the bottom of your glass.  Put too much water in the alcohol enhanced fuel and eventually it too drops out.  As it goes it can also unlock the alcohol/gasoline affinity for each other and drop out a proportionally higher amount of water than you’d expect.  Up to that point it was a stable mixture.

 

In this case the fundamental problem isn’t that there is alcohol in the fuel it’s that too much water got in the tank.  Waterlogging would happen way sooner in a tank that is filled with straight gas, but the effect is highlighted in the alcohol system because the split can happen suddenly and impressively.  This has been particularly exciting in the boating world where water contamination of fuel can come from rain ingress, humidity absorption, condensation in the tank, and water leakage into the tank from entry through the boat’s many vulnerable spots.  Hit the tipping point for the mixture in the tank and the water drops to the bottom where the fuel pickups deliver it to the engine.

 

I see online a lot of talk about how ethanol fuel pulls water out of the ambient air, but I don’t know how significant an issue this really is.  I suspect it’s pretty trivial compared to water ingress from other pathways.  High potency ethanol alcoholic drinks don’t really exhibit a tendency to suck water into them from the air.  Tanks that aren’t stored full or capped do breathe as temperatures fluctuate and can therefore condense humidity on their walls.  This is a real source of water contamination but is easily managed in frequently used vehicles.  Or the tank should be stored nearly full to minimize the volume of breath it can take during each cycle.

 

The variations in solvent properties of straight fuels and alcohol spiked fuels can affect containment materials.  Older hoses and gaskets are certainly susceptible to dissolution by the alcohol.  I suspect that there are coatings on carburetor floats that don’t agree with the alcohol too.  Modern engines have updated materials, but older ones didn’t have to deal with this when designed so can be problematic.  This is a definite problem on older boat gas tanks that are made with older rubber and plastics.

 

I do not have much understanding of alcohols’ contributions to corrosion, but I see it mentioned all the time.  I assume it’s the concomitant availability of water that influences corrosion in alcohol fuel systems but I don’t really know. Corrosion in general is a complex subject and not very well understood by those outside the specialty.  I literally had classes and have read books devoted to it and I am far from understanding the magic and mysteries of why some things do what they do.

 

In the interest of full disclosure, I do periodically buy the canned fuel from the big box stores for my 2-stroke equipment.  It’s not so much a concern about ethanol as it is laziness and not wanting to have a can of mixed gas sitting around that I don’t use very frequently.  The cans are strong little suckers and have a nice cap that seals tight and I don’t have to worry about them.  And the laziness thing…

 

I have bought the 4-stroke canned gas too, but that was just to tinker with it to see if I could detect any running quality differences in my lawnmower.  I couldn’t.  And it was also convenient.

 

I don’t want to sound like I deny that people are experiencing issues when running their equipment on ethanol extended fuel.  I do suspect that many of the issues are existing problems that are just unmasked by the quirks of the fuel.  And some of them are probably built up moisture or debris inside the fuel system that is liberated by the alcohol.  I’ve just not experienced it personally.

 

Granted, I have let carburetors sit with gas in them that eventually goes stale, decomposes, and evaporates.  Ethanol fuel or not, this is bad practice and a recipe for problems.

 

Steve

Edited September 28, 2023 by wh500special

[davem1111 1,943]

1 hour ago, wh500special said:

[...]

 

I don’t want to sound like I deny that people are experiencing issues when running their equipment on ethanol extended fuel.  I do suspect that many of the issues are existing problems that are just unmasked by the quirks of the fuel.  And some of them are probably built up moisture or debris inside the fuel system that is liberated by the alcohol.  I’ve just not experienced it personally.

 

Granted, I have let carburetors sit with gas in them that eventually goes stale, decomposes, and evaporates.  Ethanol fuel or not, this is bad practice and a recipe for problems.

 

Steve

 

Steve, that is an awesome write-up. Thank you. I'm going to copy that and keep it handy to review whenever these kind of fuel questions come up. 

[wh500special 2,076]

Thanks for the compliment.  It is truly appreciated.  
 

While I’m pretty confident in what I’ve stated, I’ve not spent my career becoming an an expert on this specific topic.  But I have had enough technical exposure to this sort of thing to have perspicacity on these issues. 
 

That said, be sure to look around at other sources of information too.
 

 And, of course, remember that I’m just some guy on the Internet!

 

Steve

[Handy Don 10,786]

11 hours ago, wh500special said:

And, of course, remember that I’m just some guy on the Internet!

Steve, we’re ALL just some guys on the internet, right? But "some are more equal than others”, if I recall Orwell correctly.

I appreciate the time you took to compose that post and share some of the knowledge you’ve built up. Thank you!

 

[wh500special 2,076]

1 hour ago, Handy Don said:

 "some are more equal than others”, if I recall Orwell correctly.

 

 

 

Oh my gosh!  An Orwell reference.  Love it!  But I must admit I'm more of a 1984 guy myself...

 

Winston