Hi. Could anyone give the proper procedure for cleaning a gas tank? My father's 77' sat for a few years and when I rebuilt the carb, I noticed rusty looking gunk in the bottom of it. I also changed a very dirty, rusty looking fuel filter as well. I know seafoam will help, but do I fill the tank up and then use and take a chance on gumming up the carb again, or do I just put a few gallons in and add the seafoam to that? Thaks guys (and gals I've noticed ).

 

I wouldn't mind knowing this too. As I was taking my carb apart the other night, I stuck my finger in the reservoir to find that it was filled with a wet, gas smelling brown soot.

Sounds like my tank is full of rust too

 

If the tank is in REALLY GOOD SHAPE, I would call a local radiator shop and see what they would charge to flush it. If it is in rough shape or needs to be repaired, I'd look into a new tank. They are readily available and fairly reasonably priced.

I flushed a tank off an old tractor using some over the counter products from NAPA. Even after the flush, I kept clogging fuel filters because the flush just didn't remove all the gunk from the tank. Ended up having to replace the tank anyway because it turned out to be cheaper than having it flushed by my local radiator shop.

 

I'd love to hear other opinions on this as well but here's what I have done in the past - which may be right or wrong - haha.

I've emptied the tank (mine were pretty much empty anyways) and then hit whatever rust I could with a wire brush attached to the end of a stick. I've then dumped a few random nuts and bolts in there and put some water in then shaken the thing for a while and dump out the water and gunk that comes with it. Add more water and shake again. Repeat that a couple times then empty as much water as you can out then pour rubbing alcohol in an swirl that around. It will help all the water evaporate out of the tank.

For the tanks with really old fuel/varnish that won't come out - try dumping in Berryman's Carb dip and swirling around. Just don't get it on you, your clothes, eyes, etc!

 

Interesting method. You didn't pour anything inside the tank to help prevent rusting from happening again?

My tank is probably rusted to hell on the inside because I had a massive amount of rusty sediment inside my carburetor's fuel reservoir last night before I started cleaning it out.

I really want to hear how people did this, because I really need to know if I need a new tank or not.

After cleaning my carb, I don't really want to repeat the process because my fuel lines are gunked up with rust.

 

I've never used this but thought this might be more inline with what you guys are wanting to do.

Gas Tank Sealer Kits

Plus there are FAQ's, safety instructions, and product instructions on the page.

 

Anyone else have any suggestions?

 

WOW!! glad you caught that. I just remember seeing it in their catalog. Had it in the back of my mind to use on my F-350 build. Guess that is out now. Guess if mine are bad looking inside, just be better off getting new tanks and be done with it.

Sorry for the bad link there!

 

Hi again. I just dropped my gas tank (really did, kind of). If you have rusty looking sediment in your filter, just go ahead and remove your gas tank for inspection. I thought I had a great looking tank from what I could see. When I really started looking, I found one small corner that had completely rusted through from the inside. Since it started from inside the tank, it looked pretty good on the outside, just like rust under a painted surface. Rust is like a hollow point bullet, small hole on one side, huge problem on the other. Now to run up to Dennis Carpenter's and pick up a new one (ouch). I'll keep everyone up on my big adventures in the world of a newbie restoring his Dad's old truck. Really guys, it is just nuts and bolts and patience. Good luck and wish me the same.

 

Well that stinks. Good luck to you as well getting a new gas tank, because I just started writing a post on how to solve the gas tank issue. I found the perfect solution for our "gas tank woes".

Too bad you're not going to be able to use it now . I'll keep writing it though an then post it as soon as it's done.

 

No big deal man. Just thought I'd pump the brakes on that idea because I noticed it immediately. I wouldn't want you using that idea.

I think I found the solution to all our gas-tank woes without putting a hole in our wallets. I can't believe I didn't think of this... and I've got 2 years of university chemistry under my belt .

Today's presentation is brought to you by the letter: E.

The letter E is for Electrolysis.

Electrolysis: "the passage of an electric current through an electrolyte with subsequent migration of positively and negatively charged ions to the negative and positive electrodes". Courtesy of www.dictionary.com

Basically the process reverses oxidation (rust) on your gas tank, but rusts another object in place of your gas tank. Essentially what happens is you have what's called a "sacraficial anode" (the thing that rusts instead of your gas tank). During the process, this "sacraficial anode" rusts away while your rusted tank has its rusty flakes and chuncks literally flake off like dandruff.

The process is very simple and only requires a few things:

1) Baking Soda (or washing soda, either will work)

2) A Piece Of Metal That Will Fit Through The Throat Of Your Gas Tank (I suggest using rebar or a tublar shaped piece of metal *Note* DO NOT USE STAINLESS STEEL AS THIS PROCESS CREATES A DEADLY CHEMICAL GAS THAT IS VERY HARMFUL)

3) Water (Tap water will work)

4) Gas Tank (must be detached and have all other materials taken off of it. Only the gas tank itself is used for this process)

5) A piece of wood (2X2 is preferable for this since it's small and will not take up too much room)

6) Wire Hanger (*Note* This process will destroy your hanger, so use one that's not going to make anyone mad.)

7) Battery OR Battery Charger (The charger works better because you can control the process *BEWARE* Improper use of this process can lead to a dead Battery Charger SO PAY ATTENTION!)

Process:

Start by taking your gas tank off of your truck. Everything needs to come off of the tank itself for this to work properly (I.e. All lines, breathers, the sending unit, etc.)

Now you need a place to stand up your tank with an opening at the top of the tank so that you can hang your piece of metal (sacraficial anode) inside it. Make sure that the only opening in the entire tank is the one at the top (once it's stood upright). All other openings need to be clogged off so that none of your electrolyte solution (baking soda and water) will leak out. To clog off the other passages, just simply duct-tape them off or clog them with a rag, then duct-tape. Any method you see fit (provided it works) will work, it just shouldn't be able to leak.

Now that the tank is off, you can mix up your solution of water & baking soda (electrolyte solution). I would highly suggest filling the tank with water, then adding 1-2 cups of baking soda. The more the better in this case. This will create a solution that electrons will flow through very easily (electricity)

After you've got the tank filled with your electrolyte solution, it's time to get set up to make that rust go back to where ever it came from.

This is the tricky part, but once you've got it, you're home free.

Double check: is tank is proped up, with the open end at the top?; your electrolyte solution is inside the tank and ready to go (baking soda and water) ?

If so, proceed. If not, go back to the top and start reading over what you've missed because this is important.

Make your wire hanger into a long, straight (doesn't have to be perfect) piece of wire.

Tie one end around the piece of wood you're using (most preferably in the center), and have the other hang below the center point of the tie point on the wood. I.e. Have it so that the wire looks like it's a laso around the wood, but the long extended piece should be hanging directly below the tie point.

Now, use the end of the wire that's hanging down and tie your sacraficial anode to so it's hanging from the wire.

*NOTE* your sacraficial anode needs to be hanging in a position that can fit through the opening in your gas tank.

Now for the tricky business. Lay the piece of wood on the gas tank, but have the sacraficial anode go inside the tank and submerge 1/2 to 3/4 of it in the solution.

*NOTE* You may need to heighten your sacraficial anode at this point to make sure that the WIRE HANGER IS NOT IN THE SOLUTION WITH THE SACRAFICIAL ANODE. Only have the 1/2 or 3/4 of the sacraficial anode hanging in the solution. If need be, keep adjusting your wire hanger length and placement of the anode until you get this right.

**** Make sure that the wire hanger and sacraficial anode DO NOT, I repeat, DO NOT TOUCH THE GAS TANK. THIS WILL NOT WORK PROPERLY IF THE SACRAFICIAL ANODE OR WIRE HANGER AND THE GAS TANK ARE TOUCHING!!! ****

Now that we have the tricky part out of the way, it's time to watch this process do its deed and let you sit back with a cold one.

This part again, VERY IMPORTANT.

Hook up the POSITIVE ALLIGATOR CLAMP to the sacraficial anode (1/2 or 1/4 that's sticking out of your solution, or the wire hanger will do).

The other, NEGATIVE ALLIGATOR CLAMP, connects to your gas tank itself.

Set your battery charger (if you're using a battery, you can't set anything) to 6 amps. Now, turn on the power to the battery charger (if you're using a battery charger).

The electrolytic solution should start bubbling and fizzing. If not, wait a small while (five minutes) and it should be by then.

IF ITS NOT DOING ANYTHING, GO BACK UP TOP AND READ OVER WHAT YOU DID WRONG, BECAUSE I'VE PROVEN THAT THIS WORKS.

Leave the solution bubble and fizz over night, then turn off the battery charger or un-hook your battery.

You should now see a brown-ish solution instead of a merky/milky-white solution. This is your rust! Horray!

Empty out your gas tank and repeat the process if you see fit, but you should be fine after one treatment.

Now comes the time to use someone else's information cause I'm tired of typing! Haha.

Follow the rest of what's on this website. It will work, and it's highly recommended by MANY MANY body shops and other forums.

Here is the link: DIY Fuel Tank Restoration

*Note* Read through the website to complete the process, otherwise you will find that you gas tank wants to "flash rust" where it starts getting small rust spots on the inside agian.

EDIT: More Notes: You're not done yet! If you leave your gas tank like this and continue to use it, your gas tank will re-rust and you'll have a thinner gas tank and the same issues you just tried to solve!

You're going to need to buy some POR-15, and some MURATIC ACID!

If you want, you may be able to find a POR-15 Gas Tank Kit which comes with everything you need for the secondary part of this post. This will solve your fuel tank problems, but you should also consider the fuel filter now and your fuel lines.

I HAVE MOST DEFINITELY PROVEN THAT THIS PROCESS WORKS. ITS SIMPLE CHEMISTRY THAT I'VE PROVEN WITH MANY LABS WITH IN UNIVERSITY AND HIGH SCHOOL.

If you don't believe me, check it out for yourself. Google - Gas Tank Electrolysis.

Let me know how this works for you guys!

 

I've used the electrolysis process for iron based materials. It works great. The problem I see for gas tanks is the deposits on the bottom of the tank. Who knows what fuels were used in them, including lead based fuels? I don't believe the electrolysis will remove these deposits from the tank. My experience with the store bought flush kits is that it seems to just be enough to break the stuff loose and clog your fuel filter.

Yeah, I know a new tank or having a pro clean the tank cost a few bucks. But in the long run, you'll be further ahead money wise, cause you won't be clogging fuel lines, filters, carbs,l etc.

 

No, you're right. This will only take off the rust particles. But, that's why I posted the link to get to the website where it shows exactly how to use acid to clean the tank up a bit more on the inside, and get the rust off of the actual metal.

I've spoken with many people about steaming or power cleaning the gas tank. Not worth it one bit. I'd rather spend $50.00 and do it right myself than have to spend $100.00 to $200.00 on a new tank or cleaning it through someone else who connects a few hoses and walks away.

If your gas tank is dirty, chances are that you lines need blowing out/ changing anyways. This is just the cheapest way to get it done for those DIYer's.

I'm interested to hear what the names of the kits were that you used on your tank. I'm looking to purchase one myself, but I can't seem to find the POR-15 kit I was talking about.

 

Sorry, This was about 10 years ago. I bought the kit at my local NAPA store. Really didn't work at all. I know POR does sell a kit, or at leas they used to. If you call POR direct, they should be able to get you more info.

 

Alrighty. Thanks for the info help and for reading my massively long post. All that info is really hard to get across.