Old Diesel vs Old Gas

Over the years, Ive had more issues with old gas than old diesel. I cant think of a single time Ive had any trouble with old diesel setting for a year or more causing starting or running issues. Gas on the other hand, Ive been burnt many times from gas gumming up the carb - mostly small engines.

Whats your experience with tractors and smaller engines with old diesel in the tank?

This comes up frequently. The usual strong consensus is that fifty year old diesel is good unless it is biodiesel, and five month old gas will probably have absorbed water. Speaking of small engines if you think that you could have condensation in the tank open the little bleed screw at the bottom of the filter bowl and let it out. The key is to have your tank full when in storage.

I see and get free lawn mowers that wont start. They run last year they said but wont start this year. Its bad gas that stinks and has moisture in it. Money in my pocket.

I don't let gas sit around for more than one year.
My 73 year old Old zenith metal carb on Farmall have no issues with E-10.
Carbs on generator are made of 2 different metals.
Just my opinion, drain carb after using them. It takes 2 metals and an electrolyte to make a battery. I think e-10 acts like an electrolyte.
The two different metals shows signs of ozidation/reduction.

Annually I drain the gas in both generators and my Jubilee, that is in retirement. Use that gas in other tractors or mowers. I never let a gas tank sit empty.

As far as I'm concerned, I hate small engines. I keep as few of them around as possible. The ones I do have around, I always try to burn fresh gas in them.

You want to have some misery in your life, just have a bunch of small engines around (more than needed). Weed eaters are the worst. Either they won't run, or the string don't work. And of course, their never fun to work on. Kind of like the old saying, about like working on a foreign car.

I won't go into the science of gas and diesel. But gas is just naturally going to go bad over time because of the science of it.

On my tractors that sit for lengthy spells, I took to siphoning the tank dry. Dump the gas in one that I'm using. If the gas just in the carb evaporates, not enough left in there to really give problems.

Use a true diesel, it will last... Do not use a Biodiesel. If let sit over time, it will plug up everything.. Gasoline; use E-91 in your lawn-mower and trimers, no ethanol, will start easy and gas last longer..

(quoted from post at 06:28:59 09/02/23) As far as I'm concerned, I hate small engines. I keep as few of them around as possible. The ones I do have around, I always try to burn fresh gas in them.

You want to have some misery in your life, just have a bunch of small engines around (more than needed). Weed eaters are the worst. Either they won't run, or the string don't work. And of course, their never fun to work on. Kind of like the old saying, about like working on a foreign car.

I won't go into the science of gas and diesel. But gas is just naturally going to go bad over time because of the science of it.

On my tractors that sit for lengthy spells, I took to siphoning the tank dry. Dump the gas in one that I'm using. If the gas just in the carb evaporates, not enough left in there to really give problems.

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Where do you get a siphon that will siphon a tank dry???? Every one that I have ever had leaves a half inch which is a gallon at the bottom. That is where the water is.

My local Maverick gas station sells non-ethanol fuel. It costs a bit more but I can leave it in my 8N and TEO 20 all year and they run fine. It also works well in all of my small engines which can be left in the sun for several weeks at a time and still run.

Diesel evaporates very slowly. Gasoline, with much higher volatility, evaporates continually. As it does it leaves behind ever greater % of the additives and heavier hydrocarbons. Alcohol is light and evaporates as well. The alcohol fuel when fresh can absorb water and keep a system water free when it is used normally. Two things cause issues: non-ethanol fuel won't absorb water at all so in a damp climate/rain environment water will accumulate in tank bottoms. (the reason we purchased Dry-Gas gas line antifreeze). It also evaporates and leaves behind varnish like coatings on fuel system parts if left for long times and drys out.
Ethanol fuels When carrying a % of water also evaporate when they do, the alcohol evaporates faster than the water, at a specific concentration, the water alcohol compound forms a nasty slime like goo. So both have issues and both require understanding.
I have used ethanol blended fuel in every thing I own for 35 years. I leave my tanks full in everything but weed eaters. I store my 51 GMC and 57 GMC and Motorcycles all winter, and do not have issues at all with fuel. The period of transition to ethanol happened in California and Colorado. The truck was used daily and never stumbled as varnish was rinsed out from MTBE and some Methanol that was used in Colorado in the early days of cleaning up the environment. Jim

Good summary! My experience is similar.

Thanks for the replies!!!

Maybe I shouldn't of used the word dry. But
I siphon out all I can get by just
siphoning. You can get most out with a 3/8s
rubber hose.

I don't siphon to get water out. Not the
purpose. I siphon to get the gas out so it
don't go bad over time. The small amount
that remains won't cause problems if it
evaporates, and if it don't evaporate,
there won't be enough of it left in there
to mess up the fresh gas when it gets
dumped in later.

Water problems would require different
tactics.

I use regular non ethanol gas in everything except my pickup including my weed eater. I use Primrose stabilizer and some of my engines sit unused for a couple years. Since I've started using Primrose, they will start like they've been run a couple days ago.

one of the reasons I like my propane tractors,, the fuel don't go bad, or get stolen
sometimes a pain to keep the valves in good condition to keep them from seeping a little tho...