How do I clean inside of gas tank?

[HGDMARTN]

I know this is not diesel related, but I want to tap into all the expertise on this site. I have a '74 Dodge motorhome with 2- 50 gallon gas tanks. Both are slam full of rust, leaves, crap, etc. What is the best and cheapest way to clean these and prevent the garbage from returning? I already hosed the first one out with limited success due to the baffles. I then tried to go to the moon without a rocket when I stuck my sandblaster nozzle in the tank. Wow- how stupid can I be? Got real lucky and sure will not try that again. My next plan is to strap the tank to my tractor tire and load it up with rocks and sand. Then jack it up and let it spin. But, will it build static and blow again?

I have asked local shops but nobody can boil out a tank that large.



Thanks in advance for the information.



David

 

[RichB59]

BB's

I would remove tanks and use BB's the kind you shoot from a Daisy air rifle. You would need help. Put a couple of packs of BB's in the tanks with a gallon fuel and slosh it around real good , repeat a few time it will take out the rust and scale. I have used this method on old tractor tanks and it works good.



LOL Rich

 

[illflem]

I cleaned and treated a rusty 15 gallon tractor fuel tank with a four step treatment system from a motorcycle shop, cost about $20 and I had enough left over to do 2 more tanks if I ever need. Your strapping to the tractor tire is a good idea if the tire will rotate slow enough so the material you use (I used a couple of handfuls of 5/16"nuts) has time to fall from one end of the tank to the other. I wouldn't use sand. Of course remove the sender and pickup tube, cover the hole with duct tape. Also go in reverse or turn the tank over. You do this with a dry tank for at least an hour. I strapped my tank to an electric motor with a gear box that turned at about 5 rpm. Maybe you have a PTO implement that turns slowly you can strap to. After removing the nuts and busted loose rust by shaking and compressed air you add acid from the kit then rotate for another hour, you do this until the acid comes out clean, took me three times. Straight swimming pool muratic acid will work. The tank inside looked like brand new bare steel after this. Next step was a solvent to remove excess acid and prepare for the coating, just add it, slosh it around and dump, you can reuse the leftover. The coating that comes last looks like white latex paint, after adding it you slowly rotate the tank end to end, side to side until the coating is everywhere then leave the tank to drain, you can also reuse this part. Tape over any rusted though parts is said to make a leak free permanent seal. After letting the tank dry for a couple of days it's ready to go. I did it with an air hose slowly hissing inside. Do all of this with good ventilation and eye protection, all the materials are nasty. I did this treatment over five years ago, the tank is still absolutely spotless inside, no more clogged up fuel filters. At one time JC Whitney carried a similar tank treatment system, you might check them out. If I remember right the stuff I used was called Tank-Kleen. Another alternative is to replace with new plastic tanks, more money but a lot less work. Doing my 15 gallon tank took most of a day.

 

['956Wheel]

Tumble it!

I had a gas tank problem like that and cleaned it with lots of 3/4 gravel, water and dishsoap... we city boys had to take turns shaking and rolling it... no tractor! Arms hurt for a week!



Good luck,

Mike