Cleaning The Fuel Tank

The last time I fired up the CJ5 was more than three years ago when we started the house. Getting ready to fire her up again and assess for restoration. First thing on the list is cleaning out the fuel system. Tank was in good shape back then but there’s no doubt it needs drained and cleaned. What’s your process for getting the fuel system in order?

 

I have had good results cleaning a tank with "The Works" toilet bowl cleaner. The stuff will remove the varnished gasoline and every bit of rust, but be aware the rust may be worse than you think and there may be places in the tank where rust is the only thing keeping it from leaking. With the rust removed you may end up with pin holes in the tank. This happened for me with my CJ5 tank, but I have used the stuff to clean out other tanks with no issues.

First step is to drain the old fuel out of the tank, remove the supply line and the strap and take the tank out of the Jeep.

Plug the drain hole and supply line hole with pipe plugs, rinse it out with a garden hose to remove loose debris. Then add two bottles of "The Works" put the cap on the tank and slosh it around for a while. Let it sit for a few hours going out to slosh it around for a while every now and then. Then dump the contents, thoroughly rinse it again, then dump in a box of baking soda, refill with water and let that sit 30 minutes to neutralize the acid in the cleaner. Rinse again, remove both plugs and the cap, drain it, and blow out as much of the water as you can with compressed air, then set it in front of a heater until it is dry inside.

You can either flush out the fuel line, or replace it with a new one.

Install a good filter, preferably between the pump and carburetor.

When I got the pin holes in my tank I bought one of the reproduction steel tanks available at most suppliers, but it developed a leak around the seams within a few months. A few years ago I bought a reproduction steel tank for my CJ2A and the bung for the supply line was only soldered half way around and it leaked badly until I pulled it and did the job right. I won't buy another reproduction steel tank unless I know for certain it is not a Omix-ADA import.

I ended up buying a MTD plastic tank for that CJ5 and am very happy with it.

Were I to buy a new steel tank today, I believe I would buy it from Debella Jeep Parts as he has "OLAP" branded tanks, which I believe are made in Canada, and are very likely much better quality than the Omix-ADA imported crap most suppliers sell.

 

Don't fix it if it ain't broke.

A good filter will prevent carb problems. Open the drain once, if it has one. Use dry-gas and/or Seafoam.

If the tank develops an issue, fix it when it does.