OK folks, I really did a stupid here and after some consideration, I put about a gallon of old gas in my truck and out of a boat tank, given to me by a neighbor.
Immediately, truck only fired a little and then wouldn't start at all. I can only surmise that there was water in it, to act like that. There's between 1/4 and 1/2 tank in the truck and I can only think of draining it draining it completely, unless some of you have a better idea. Thing is, I'm not even sure how to do that, unless it has a drain plug. Maybe an inline connection somewhere, lower than the tank, like I once found on a Vette for draining it?
Yes, I know, dummy here should have put the gallon or so, in a jug and checked it out later for using it in the lawn mower. Stupid is, as stupid does, or something like that!
It was after dark last night and thought I'd get some ideas here, over coffee, before going to look at it, this morning, so any help will be appreciated.

 

Only a gallon? Fill it up with good fuel and add fuel treatment, you should be fine unless the fuel you put was a 2 stroke mix lol

 

I thought of that, but really scared to have a full tank and then have it still not wanting to start. So what happens if I give it a good dose of fuel treatment with the way it is?
Still, can you really turn water into gasoline and do understand if we're talking just a bit more than heavy moister?

 

First, i'd siphon out as much gas as possible.
If you're sure the old gas is water contaminated and not just stale, then try adding a couple bottles of Winter fuel de-icer along with a small amount of fresh gas.
Wait a while for it to mix then siphon out again as much as possible (might want to bounce the truck to mix it better).
Then i'd add a few gallons of fresh gas along with a 1/2 bottle of de-icer.
The 100% alcahol in that stuff readily combines water with gasoline
.
If its just old stale gas then adding fresh gas would probably work after cranking a while.

If that old gas is that heavily water contaminated, i'd worry about hydro locking the engine. Not good.
Might want to pull the spark plugs and disable the ignition somehow while cranking the engine for a while.

Don't feel bad i almost did the same thing with some old lawn tractor gas i wanted to get rid of.
At the last minute decided not to.

 

2 stroke wont hurt it at all.

If its water, dump in some Heet and fill it up with 91-93 oct.

Drive it.

 

[QUOTE)Drive it.[/QUOTE]
No oil in it, but It's gotta start first......lol

 

I found a couple of hoses in the attic, so hopefully there's not an obstruction of some sort in the fuel neck.
This sh......happens on a day, as I'm getting ready for a long weekend and RV trip. Lucky I don't need the truck and may have to wait until I get back for taking a real looksee, so don't give up on me, if out of here after tonight, as I will get back with some kind of results. Going to give some shots at it today, however.

 

UPDATE:
Made some time for getting back at it this afternoon.
First did the siphoning routine for all I could and which amounted to about 8 gallons and judging to be about right.
Then with adding 5 gallons of fresh 93 octane and little by little with 1/2 bottle of HEET.
Tried starting and wouldn't even fire.
Got it to sputter with a few shots of engine start fluid, so now know it's fuel related and not just some consequence..
Then realized if I turned the ignition off and on a few times I could get it to run for about 3secs.
Over and over again with this, until I realized I could keep it running, but barely, at 1/2 throttle.
Finally, the RPM goes up, but for just a bit and then back to where it was.
Only for a bit though and then viola, it almost screamed before I could let off the pedal and settled down for a nice idle.
Let it run for awhile and with having since put the rest of the HEET in, proceeded to the station for adding 15 more gallons of the 93 stuff.
Gave her hell down the road for a mile or so and turned around.
Now noticing that the fuel gauge shows only a 1/4 tank and thinking that it has a float in the tank, that I damaged with the siphoning hose.
Once home, I shut it down and with turning on the ignition again, it read almost full, so all is well.
Many thanks to all and especially to Moparado for laying out the details.
I was almost convinced that I had another problem and still can't figure why it didn't initially start, run and then sputter for a bit before dying.
Won't be doing that again and now have a lot more respect for good fuel. Neighbor was probably off a few years with his 6 mon old fuel, as well.
Hopefully this account of my ordeal will help out someone else.
Now what to do with all that old fuel and do want to check it out for water and then maybe use some additives, for trying it out in my lawn mower.

 

 

Water is heavier than gas, fyi. Probably had some on the bottom yet.

Dont "giver hell", just drive it.