Fuel transfer tanks, a question a about use

[martin_95037]

I do tractor work on the side from my normal 9-5. I am considering buying a transfer tank to put red diesel in.

Let’s say I put 100 gallons of diesal in the tank, I blow through it in 3 months. I go to Reno and want to fill it with Ethanol-free gas to put in all the old equipment that have metal tanks.

Should I be concerned about the very small amount of diesel that is still in the tank IF, IF I choose to fill it up with gasoline, then re dispense into other tanks. All these engines are dumb and carbureted.

Now if I do it the other way around of putting diesel in gas tank, I know to let the tank bake in the sun with the cap off so all the gas fumes escape.

 

[bodabdan]

Sorry for the delayed reply. I would not try what you're describing for a couple of reasons.
First, the potential to damage something with the wrong fuel. You could end up with a burned piston, particularly on a diesel with gasoline contamination. Transfer tanks usually don't pull off the very bottom of the tank, and many can't be filled to the top to leave room for expansion. This limits your ability to dilute what's left in the tank. You mentioned leaving the tank in the sun to evaporate the fuel. Set one of your gas cans outside without a lid and watch what happens. The lighter components of fuel will evaporate, but some heavier stuff will take much longer and will probably varnish before it evaporates.
Secondly, there's a limit on how much gasoline you can carry without declaring it as a hazardous load, requiring placards and the full hazmat protocol. The limit is around 36 gallons IIRC. When you look for transfer tanks designed for gasoline you will see very few options and they will cost more due to regulations.