truck sitting 24 years, cleaning out fuel tank

[mike16]

my 68K20 has 13k miles on it. its been sitting for over 24 years. the current batch of fuel in the tank is al least 1 year old. I dont know how much is in there. but I want it out befor I put fresh gas in and start it up. what has any one else done to remove the old gas. what solvents work to remove the shellac that no doubt is also in there.

Also... I have saddle tanks that I can tell are much worse in terms of old gas.

So how to remove old gas... and how to clean tanks.

I want to avoid actually removing any of the three tanks.

[Grumpy old man]

You can't completely drain the tanks and clean them without removing them from the truck .

[Gmc.guy]

I have an electric pump that I put hose nipples on and I unhook the hose and hookup at the fuel pump or tank or a 3/8 hose down the filler hose. pump out into jerry cans or old jugs.its a framerail Ford pump I got for 10$ at a yard. I just made leads with a switch and clip to a battery. It's nice to drop an empty tank you can pump through a clear fuel filter to see what junk is coming out too It won't drain it all If you want it super clean you will likely have to pull them and then sending units.

[Gmc.guy]

I have seen kits for cleaning tanks that have a solvent or acid? And some type of sealer. I cannot recall a brand but that might help you anyway

[Fly By Night]

Depending on how bad it is I would probably get it out, refill with fresh and keep a close eye on the fuel filter. 21 gallons of fresh fuel ought to pretty dilute down whatever is left over.

[71swb4x4]

I had the same deal with my Blazer, and also didn't want to remove the tank. I ended up removing it and am very glad I did. The tank was a mess. I used the Por 15 gas tank cleaner and sealer. It worked well.

[Grumpy old man]

Kreem tank sealer is used after the tank is clean , once out take the tank to a radiator shop for cleaning

[1968aj]

I find it cheaper in the long run to put in a new gas tank.

[special-K]

If you are concerned about shellac formed on the walls of the tank, the only way to do it right is remove it. Taking the seat and tank out is easy. I'd take mine to a local radiator shop to have cleaned and checked, but my guy has retired. I have used products made for this with good success. I guess I'm back to that.

For just old gas concerns, I have drained and purged with air nozzle (leave cap on), pour a couple fresh gallons in, drain, purge, 5 gallons of Cam2 with a bottle of Sea Foam and that has worked well.

[mike16]

the two sadle tanks I was going to take to a radiator shop. sucking it dry was my first goal,