Tricks for cleaning old fuel tanks?

[Branchchipper]

We are beginning restoration work on the first of several older gasoline-powered machines. All have smallish steel fuel tanks with much solid crud inside- are there any tricks for cleaning this stuff out?
Two are mid-60's Cub Cadets- tank replacement is not an option, and there is no rust-through or even major external pitting on the originals. Any advice is appreciated.

 

[Egon]

The best would be to take them to a proper shop for clean out and application of an inside coating.:thumbsup:

Steam cleaning.

Putting in some diesel and sloshing around till it's clean. The cheapest maybe?

 

[whodat526]

muradic acid will do the trick and clean all the rust out and help u find the wholes if there is any in the tanks this is what i always use

 

[ultrarunner]

Radiator shops clean and repair fuel tanks... at least the ones I know.

I've also used lengths of chain and TSP to remove fuel tank build-up... the chain helps to scour the tank as it is moved about.

 

[rrrkkk]

Google POR15 stands for pain over rust, they have fuel system cleaners and rust treatment as well as sealers. Wonderful stuff kinda $$$$ but work well

 

[Chooglin]

fill the tank 1/4 of the way with small rocks/pebbles and kerosene and shake it for as long as it takes to clean it out.

 

[Jeff Lary]

I agree with the cheep method I have used a couple of hand fulls of old or new nuts bolts and washers and diesel fuel as well as small crushed stone some may call it pea stone or just sand then take turns shaking the H*!! out of it. I just did this to my coolant resivour worked good

 

[Jim Thompson]

Some motorcycle shops sell tank repair kits with polyurethane for stopping/ preventing leaks after the tank is cleaned. I second the loose bolts/ nuts and the muratic acid. If you're going to use the acid, you may want to dilute it. remember to add the acid to the water, not water to acid and use in very well ventilated area.:thumbsup:

Jim

 

[skipmarcy]

I used a couple of things when I cleaned my old IH 340 utility gas tank years ago - I had the best results from using some Naval Jelly + some good sharp-edged gravel from the driveway and rinsed very well and dried before using a gas tank sealer. This quart of sealer was around $35 but it will do about 3 or 4 automotive sized gas tanks, can't remember the name of it to save my life. You pour some in the tank and of course turn it all around to coat the inside everywhere then pour the remainder back in the can. It forms a tough, very thin membrane and seals any leaks you might have. I did that tank about 13 years ago and the current owner says it's still holding well. I bought the can of sealer at my NAPA dealer back then.

 

[PILOON]

Many of the smaller tanks are made of 2 halves that are soldered together.
If so, you can de-solder making internal cleaning a simpler task.
Also once cleaned it is not that difficult to solder coat the entire inside using acid flux and then re-soldering the 2 halves.
If the tank has a folded or beaded joint for the halves, simply grind away the bead and to re-assemble solder the halves back together.
I have done this restoration more than once and it works just fine, not cost effective but sometimes the only easy solution.

 

[Egon]

That one is a good solution Piloon.:thumbsup:

 

[ultrarunner]

I used a couple of things when I cleaned my old IH 340 utility gas tank years ago - I had the best results from using some Naval Jelly + some good sharp-edged gravel from the driveway and rinsed very well and dried before using a gas tank sealer. This quart of sealer was around $35 but it will do about 3 or 4 automotive sized gas tanks, can't remember the name of it to save my life. You pour some in the tank and of course turn it all around to coat the inside everywhere then pour the remainder back in the can. It forms a tough, very thin membrane and seals any leaks you might have. I did that tank about 13 years ago and the current owner says it's still holding well. I bought the can of sealer at my NAPA dealer back then.

Fuel Tank sloshing compound is something I have used a lot over the years... everything from antique car fuel tanks, motorcycles and power equipment.

I have one that I did in the 80's that is giving me problems... seems California reformulated gas dissolves the compound into a goo... what a mess.

 

[wdchyd]

Some motorcycle shops sell tank repair kits with polyurethane for stopping/ preventing leaks after the tank is cleaned. I second the loose bolts/ nuts and the muratic acid. If you're going to use the acid, you may want to dilute it. remember to add the acid to the water, not water to acid and use in very well ventilated area.:thumbsup:

Jim

x 2......IIRC, the stuff is called "Kreem" and it comes with phosphoric acid, MEK, and the polyurethane coating stuff......

It works real good after the nuts/bolts or rocks, then solvent/ cleaner

 

[AV8R62]

I used white vinagar to remove the rust then rinsed the tank with warm water and baking soda.

 

[pheonixthree]

Just a quick word of caution if you are going to unsolder a gas tank...make sure it has not had gas in it for a long time! Flush it out. Force ventilate with compressed air or CO2.

I use CO2 from my mig welder if there is ANY odor from tank before/during grinding or applying heat. CO2 displaces the air and will not support compustion.