flushing inboard gas tank?

cookbayou

Seaman
Joined
Apr 20, 2009
Messages
50
Ive got a 36 gal inboard tank. It sat up for sometime and the fuel went bad. The other day i put a gallon of lucas fuel conditioner in it and pulled about 3 gallons of seperated fuel out. Could I just flush the tank with about 10 gallons of clean fuel and injector cleaner and it be alright? A buddy told me just to bite the bullet and put a new tank in the boat but funds are tight right now.
 

Lrider

Chief Petty Officer
Joined
May 19, 2010
Messages
631
Re: flushing inboard gas tank?

Helped a friend do that a few years ago. First find out where you can legally dispose of the bad fuel. His tank was bigger, had baffles and a lot of water (another story) we pumped the tank out into a 35 gal barrel-it there was no access to the tank except from the filler. He used alcohol (several gallons) to clean out the water, he said alcohol absorbs water. we flushed it several times, between each flush we drove the boat (on the trailer) around the block a few times to get over the baffles I guess. then he did a gas flush and emptied it. then filled the tank about half full with the 2-cycle mixture - it is still working great, only took us 3 days and the disposal fees for the gas were like 30 bucks.
 

Home Cookin'

Fleet Admiral
Joined
May 26, 2009
Messages
9,715
Re: flushing inboard gas tank?

don't know how your boat is rigged. See if this works: drain it by running the fuel line that is on the tank out the bilge drain hole. Use the bulb to prime it and siphon. Tilt the trailer up.
Remove sending unit for access, clean with a whole can or more of spray carb cleaner, move it around by raising/lowering the trailer and/or driving around.
Swab out with a rag on a stick.

Check with junk yards or fuel oil companies about disposal of bad gas. There should be marine oil recovery companies where you are that will take it. I used city recycling here.
 

cookbayou

Seaman
Joined
Apr 20, 2009
Messages
50
Re: flushing inboard gas tank?

Thanks. Now where do you get several gallons of alcohol?
 

Lrider

Chief Petty Officer
Joined
May 19, 2010
Messages
631
Re: flushing inboard gas tank?

I found the following in Boat Restoration and Building maybe that would be a better place for your questions

Was about to pull what little hair I had left out due to chronic contaminated fuel issue. Learned the valuable lesson the hard way. Go buy as many 5 gallon pails as required for fuel (with lids). Raise bow as far as possible. Rig electric fuel pump and remove as much fuel as possible through engine fuel supply line. Remove fuel tank access or fuel sending unit. Pump remainder of fuel from here. I got over 2 1/2 gallons of pure water, varnish, sludge, $@*&, etc from this point. Use cotton wiping cloths to clean and absolutely dry tank, adding a little acetone to the cloth will help. By now any water that may have been pumped out with your fuel will have settled. Pump each pail of fuel through a 21-10 micron fuel water separater rigged with a clear vinyl discharge line:D and back into the tank. Water will be visible and easily prevented from pumping. No Smoking please. This past weekend I solved my issue and salvaged over 70 gallons of fuel to boot. At $2.70 per gallon I easily paid for the $50 worth of fuel pump, hose and 5 gallon pails. Be careful and good luck. In all I ended up with just over 4 gallons of water. Just too much to deal with passively.
 

scubadiver4606

Recruit
Joined
May 25, 2010
Messages
1
Re: flushing inboard gas tank?

Ive got a 36 gal inboard tank. It sat up for sometime and the fuel went bad. The other day i put a gallon of lucas fuel conditioner in it and pulled about 3 gallons of seperated fuel out. Could I just flush the tank with about 10 gallons of clean fuel and injector cleaner and it be alright? A buddy told me just to bite the bullet and put a new tank in the boat but funds are tight right now.

Dump all the fuel then run a hose from a car exaust(running) into the tank for for about 40 this will burn off anything left in the tank safely.. .we use this process to weld fuel tanks >>>Herb Welder 36yrs
 
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