Best way to clean fixed gas tank

[DA505]

I purchased a boat that had been sitting for eight years with about 7 gallons of 2-stroke gas. Tank is fixed and non-removable. I have access toa 3"hole removing the guage. There's a bunch of loose particles on bottom of tank. I syphoned all but 1/2". Any ideas on how I'd be able to clean it out?

 

[Home Cookin']

Re: Best way to clean fixed gas tank

try to get out all the rest. spray a can of carb cleaner in there, "swish it around" by raising/lowering the tongue jack or driving around the neighborhood like a crazy man. Open it back up, syphon what you can, swab the rest out with rags SECURELY fastened to sticks, and don't use rags that are coming apart.

This will work on smaller tanks (20 gal) not sure about big deep ones.

 

[nlain]

Re: Best way to clean fixed gas tank

I would hope there is a section of deck that can be removed to get the tank out of the boat, otherwise it is going to be very difficult through a 3" hole. You really need the tank out of the boat. I know your post indicates that the tank cannot be removed, but that is what needs to happen. Be very careful working in there and do not blow yourself up. You need to get all of the old fuel out of the tank, purge the tank to remove all explosive fumes, there are two ways purge the tank, first blow air in it for a long time, second fill the tank with water, then maybe you can rig a wet or dry vac with a small hose that you can put in the tank to remove the small particles. You must get all of the explosive fumes out of the tank before you try this, motor on vac could cause an explosion when you draw air from in the tank through the vac. Be very careful if you try this, there is a very large danger of explosion.

 

[Thalasso]

Re: Best way to clean fixed gas tank

Soak up all fuel. Fill with water to the brim and that will force any fumes out that may be left. Siphon out and take a shop vac for the rest. Soak up anything left over and you will be good to go.

 

[BoatDrinksQ5]

Re: Best way to clean fixed gas tank

never would have thought of the water trick! seems like a big no-no adding water to a tank....but should be fine if you can get vac to bottom of tank. should work great!

i would do the carb cleaner first also to make sure any gunk from sides/bottom is OFF first...

also drain lines and any filters - don't want to gunk up your injectors or carb.

 

[nlain]

Re: Best way to clean fixed gas tank

The water trick has been around for years, that is how we welded/soldered leaks in gas tanks on cars and pickups. Drain, blow out a little, fill with water and do what you need to do, drain water, remount, fill with gas and away you go.

Something else, I would change the lines and filter, not just drain.

 

[jdlough]

Re: Best way to clean fixed gas tank

I used StarTron Tank Cleaner to dissolve all the particles/old fuel shellac in the built-in aluminum tank in my skiff.

http://www.iboats.com/STAR-TRON-TAN...58790832--session_id.054003834--view_id.61945

It worked great at dissolving everything, which I then siphoned out.


Unfortunately, it seems some of that gunk was plugging a leak in my tank, which became revealed after I cleaned all the gunk out.