Clean Fuel tank

[Tony 73]

My fuel tank is in great shape except for the grim that has built up on the inside. The grime is firm to touch when dry, once wet it becomes  a little sticky.
I placed a large number of bolts in it and added some fuel and have been agitating it but have not seen any reduction of the grime. I have managed to get  my fingers in the inlet hole and the grime can be removed.

What are my options ?

Ideally I want to pour in some type of liquid the will dissolve the grime.

Worst case I will use the tank as is and change  the fuel filter each month.

[Rich G.]

Replace it. It's probably one of the cheapest parts you can find. Not worth the problems it will give you.

[dodj]

Replace it. It's probably one of the cheapest parts you can find.

That's what I was thinking but shipping to Australia probably doubles or triples the cost

[EV2RTSE]

I've no first-hand experience here but have heard you can use muriatic acid or a solution of vinegar and baking soda along with water to clean the inside of the tank, and then seal it with something like this-

https://www.hirschauto.com/ALCOHOL-RESISTANT-GAS-TANK-SEALER/productinfo/GTS/

Have also heard of people "boiling out" (hot-tanking) gas tanks at radiator shops. I would think though that in addition to cleaning the inside that this would also remove or damage the plating on the outside of the tank, so then you may be needing to paint it or something.

[Racer57]

Remove from car. Throw a match at it.     

[RUNCHARGER]

I've done motorcycle tanks before. I think you use muriatic acid then roll it around with chain inside, then coat the inside. Just google cleaning motorcycle tanks and you should get some ideas.
Have you put on a body condom and then stuck a pressure washer inside and just spray the heck out of it?

[Tony 73]

Excellent replies .

Buying a replacement tank would be a great idea if I didn't live so far away from the USA.

Did think about sticking the end of a pressure washer inside the tank and going for it. Now that I think about it a friend has a washer that does hot water.

Will google motorcycle tank cleaning as well as muriatic acid and vinegar .

Cheers

[1 Wild R/T]

Problem is once you use the muriatic acid your probably gonna have a bunch of holes to solder up....  If you find yourself in that position either put dry ice in the tank before you start bringing a torch close or plumb a car exhaust into the tank... You want inert gas of some sort filling the tank to prevent an explosion...

[gzig5]

Eastwood sells a cleaning an sealing kit.  I don't have any personal experience with it but if I were going to do this, I'd want to seal it after it is clean. 
https://www.eastwood.com/gas-tank-sealer-kits-eastwood-gas-tank-sealer.html?SRCCODE=PLA00010&gclid=CjwKCAjwgdX4BRB_EiwAg8O8HfVmp9RuTqrsEjBq88HoGleyql9wlfR3bjwaLmwKBL35yKs2QFcfURoCsjEQAvD_BwE

Another idea I had was to see if you can find a company that still rebuilds radiators.  They have a tank to clean them out and would be able to solder/braze patch any holes.

[headejm]

Replace it. It's probably one of the cheapest parts you can find. Not worth the problems it will give you.

(Even understanding the logistics problems).

[dodj]

You want inert gas of some sort filling the tank to prevent an explosion...

Whitch is why you will never find me welding up holes in a gas tank.......
I'll buy a new tank rather than end up in hospital. Even with my 'free' health care...

[Tony 73]

Cheers for the inputs.

I will look into the cost of a new tank. Was looking at my front brake rotors and they are  too thin to get ground smooth which means I will have to purchase new ones. Too heavy to import myself so go though a Muscle Car parts business , will ask them for a price on new tank.

Like the idea of the radiator shop, will look into that .

Cut good size hole in  top , clean, then weld up be an idea, but risks involved not so good.

[gzig5]

You can safely cut/weld on a tank with a few precautions. I cut a propane tank in half recently with a grinder and plasma cutter and I lived to tell the tale. But if you can avoid it,I would.

[Tony 73]

to get a new tank is about $300 US ( to NZ).

The inside of the tank looks like Bitumam based underseal, kerosene when added to to it, in small container, removes the sticky dirtiness and leaves cleanish pliable material.

Thinking buy 1/2 gal of kero, make up long handle brush, clean best I can , and change fuel filter regularly .