Gas?

So according to the fuel-testers products like Sta-bil don't really do what they say they do? I don't believe that to be true because I've used the product and others of the same type in my small engines and have not had the starting problems caused by stale gas that I did in the past.


The way I interpreted the results Stabil is one of only 3 products they recommend. The issue is other products have some form of alcohol in them, which actually attracts moisture into gas. Ethanol gas already has ethanol (alcohol) in it, so with most additives you are adding more alcohol.


I talked with a couple of boat repair places and marinas - they recommend straight gas, to not let gas sit or be unused for more than a month, and that Stabil Marine to be used. They mentioned a few other products that are not commonly available.


I also talked with a local small engine shop, same thing. This place also recommended to run the gas out of the carb, and drain the carb for storage. They told me draining the carb was important, since whatever is left can evaporate and then dry in the passages/jets. Also can sludge/varnish in the bottom of the carb bowl, 1st time you run after storage can clog up jets/passages. The passages are so small in some small engine carbs (small push mowers, pressure washers, etc.), if they clog with varnish, they cannot be cleaned, carb replacement is the fix.


The above is what I have been told after I asked. One spring had to have my motorcycle carbs cleaned at a shop (not cheap), push mower carb cleaned, and a pressure washer carb replaced. An expensive lesson about ethanol gas.
 
A model A gas tank is vented to the atmosphere.

Yes, but the goal is to reduce as much as possible the surface area where the atmosphere contacts either the fuel where moisture absorption can occur, or the surface of the tank where condensation can occur. A full tank does that.
 
Yes, but the goal is to reduce as much as possible the surface area where the atmosphere contacts either the fuel where moisture absorption can occur, or the surface of the tank where condensation can occur. A full tank does that.



Have not had this happen to me, but have heard you do not want to fill right to the very top when storing. If it warms up enough, expansion of the gas can cause the tank to leak out through the gas cap onto the cowl.
 
The issue is other products have some form of alcohol in them, which actually attracts moisture into gas.

The purpose of alcohol in those products is to bond with any water that is in the tank. The same thing the ethanol in E10 does. It puts the water in suspension which keeps it off the bottom of the tank and allows it to be burned in combustion. They do attract water but almost entirely the water that is already in the tank...especially if the tank is full and the cap is sealed.

Products like HEET are essentially pure Isopropyl alcohol.

"Isopropyl alcohol is a major ingredient in "gas dryer" fuel additives. In significant quantities water is a problem in fuel tanks, as it separates from gasoline and can freeze in the supply lines at low temperatures. Alcohol does not remove water from gasoline—but the alcohol solubilizes water in gasoline. Once soluble, water does not pose the same risk as insoluble water, as it no longer accumulates in the supply lines and freezes, but is consumed with the fuel itself."

https://en.wikipedia.org/wiki/Isopropyl_alcohol
 
I was at a landscape equipment store yesterday, the owner said, do not leave gas in any equipment, lawnmower, leaf blower etc. for over a month. Should that be the same rule with The Model A, since all gas here has 10% Ethanol? I do use Sta-bil additive, does that help if its over a month in the tank?

2 Cycle engines tend to not do well keeping a gas oil mix fuel stored in them over time. It tends to gum up and I would venture the equipment store kind of had that in mind in particular. 2 cycle engines that I have, I tend to run dry at the end of seasonal use. For any 4 cycle engine that is seasonal or not used a lot Sta-bil and Seafoam are the ones I use!
 
The purpose of alcohol in those products is to bond with any water that is in the tank. The same thing the ethanol in E10 does. It puts the water in suspension which keeps it off the bottom of the tank and allows it to be burned in combustion. They do attract water but almost entirely the water that is already in the tank...especially if the tank is full and the cap is sealed.

Products like HEET are essentially pure Isopropyl alcohol.

"Isopropyl alcohol is a major ingredient in "gas dryer" fuel additives. In significant quantities water is a problem in fuel tanks, as it separates from gasoline and can freeze in the supply lines at low temperatures. Alcohol does not remove water from gasoline—but the alcohol solubilizes water in gasoline. Once soluble, water does not pose the same risk as insoluble water, as it no longer accumulates in the supply lines and freezes, but is consumed with the fuel itself."

https://en.wikipedia.org/wiki/Isopropyl_alcohol


Correct me if I misunderstand, but there is a secondary issue of the ethanol itself separating out of the gas over time. It's called phase separation. So E10 looses its ability to suspend the water in the gas, and the water and ethanol lies at the bottom of the tank.
 
Correct me if I misunderstand, but there is a secondary issue of the ethanol itself separating out of the gas over time. It's called phase separation. So E10 looses its ability to suspend the water in the gas, and the water and ethanol lies at the bottom of the tank.

You are correct from what I hear and read. I think the paradox is that if there is condensation and you run straight gasoline you will have water at the bottom of the tank immediately. If you run E10 at least you have a chance of the ethanol absorbing the condensation and holding it in suspension before there is enough water in the fuel that it gets to the point of phase separation.

"E10 can hold approximately 0.5% water at 60°F (.64 ounces in a gallon, or 12 ounces of water in a 20-gallon gas tank)," before phase separation takes place. With gas without ethanol (or HEET) you will have any water that gets in the fuel at the bottom of the gas tank right from the get go.

I'm no fan of E10, but I've learned to live with it. Full tank (E10) over the winter with Stabil in it (even though I do drive my collector cars some in the winter). Small engines left with no fuel in the tank or carbs.

The best choice is to keep driving our collector cars no matter what fuel you use. This is pretty tough in some areas, however.
 
Ok, thanks for the details. For me living in Wisconsin, I refuse to drive during road Salt season. My truck has some rust on it, do not want salt get into it.


I usually drain a few gallons in the spring before starting or moving my A, and hope to drain any water, except what can not be drained unless the shutoff is removed. Then immediately put in some Seafoam in hopes any other water gets mixed up. We all have our methods.


I do the same as you on small engines, 2 cycles I additional throw in some isopropanol and swish it around and drain it, fears of left over 2 cycle oil in the tank collecting on the bottom of the tank and clogging things up in the spring.
 
I put Sta-bil in the tanks of the toys if I remember. A snow blower sat for two years with old gas and started on the first pull - I don’t remember if it had Sta-bil or not.
I know that I didn’t use it in the T or A last fall and they both stared without any problem.
My generator sat for Over a year and started without an issue last weekend.
I think that most of the issues that people report are not due to gas.
 
My Post 22, last paragraph was definitely gasohol related, or so 3 different shops that work on those 3 issues told me. So that is why I am a believer of ethanol issues.
 
I put Sta-bil in the tanks of the toys if I remember. A snow blower sat for two years with old gas and started on the first pull - I don’t remember if it had Sta-bil or not.
I know that I didn’t use it in the T or A last fall and they both stared without any problem.
My generator sat for Over a year and started without an issue last weekend.
I think that most of the issues that people report are not due to gas.

Treating engines that way, it will likely soon be you reporting the issues! :) Some people seem to get by, I'm not so lucky. I only use it in vehicles being driven often.
 
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