Electrolysis for Rust Removal

After reading up on electrolysis for rust removal, I thought I would give it a try on the XS400 tank. Here are some pictures of the setup and how it worked. I have to add that this is extremely simple to do compared to working with the acid I used on my Seca tank.

All you need is a bucket, battery charger and the Arm & Hammer Washing Soda.

Here is the Sodium Carbonate (Arm & Hammer Washing Soda) to make plain water into an electrolyte. Just use 1 tablespoon per gallon of water.


Here is the sacrificial anode. Just a piece of threaded rod and a cap from a can of spray paint trimmed a little to fit the tank opening. This holds the rod away from the sides of the tank.


Here is the setup in operation. Fill the tank with the electrolyte solution and connect the positive clamp of a battery charger to the threaded rod and the negative clamp to the tank. It is important that the threaded rod does not come in contact with the sides of the tank. What is happening is any rust, paint, crud, sludge picks up a negative charge and then becomes attracted to the positively charged threaded rod. The rust and crud slowly start to move to the threaded rod. A lot of the material sticks to the rod and a lot of it settles to the bottom of the tank where it comes out when you pour out the tank when finished. Keep in mind that the process produces small amounts of oxygen and hydrogen, so have some ventilation.


Here is what it removed from the inside of the tank. The dried rust on the workbench is from knocking off the rod after about 4 hours. I ended up leaving it going overnight. Notice that the rod collected sludge in addition to the rust.


This bucket contains the electrolyte solution after pouring it out of the tank. In the bottom is a layer of sludge that the process loosened from the tank sides and poured out when I drained the tank.

 

Works great for getting up and residue stuck to the rust doesn't it?
That how I got the remains of my failed molasses attempt
Nice job on the anode, I made a plug out of hard foam, that looks more stable...

 

When I was gonna clean my tank, I read up on the electrolysis process. Read accounts of burning holes and such.......I just used chemicals LOL! Looks like it worked pretty good for you...

skillet

 

Gadfrey. What's it look like inside?

I'd go back and flush it with phosphoric acid now.

 

There's no need to flush with acid. The inside of the tank is spotless. As soon as I poured out the electrolyte, I blew out with compressed air and then coated the inside with MMO as I won't be filling it with gas for some time. I'm still going thru the things I need to do to start the motor for the first time.

I can post pictures of the inside of the tank hopefully tomorrow. The tank is at a buddy's this weekend who is going to try to pull out that huge dent on the left side of with one of those stud welders.

 

Ah, good ol' Mystery oil. Love the stuff.

 

cturek,

Did you electrical tape the other end or no need to since it appears that it is at a right angle & the rod was suspended inside without touching sides or bottom.....

Just wondering......

Great job...

 

cturek,

How long was the anode rod & was it a 90 degree angle....how did you ensure that it didnt touch the tank on the inside ???

Just curious........I was about to use your method.....looks like it worked well....

5ofakind

 

Eeek! That scares the crap out of me.

 

I've done two tanks like that using regualr table salt instead of washing soda. It worked fairly well and cleaned out all the rust in the tank. I used a short piece of 1/2" rebar for the rod in the tank mounted on a rubber drain plug from a sink that fit tightly in the fill hole. With a 10 amp charger, nike took pretty much the entire day to clean it out completely.
I then used rubbing alcohol (evapoates well) to clean out the tank and blew it dry inside with a blow driyer before refilling it with gas. Now as long as the tank is full when I park it, I don't have a rust problem.
The main reason there is rust inside a tank is because they are left mostly empty or drained completely before sitting for extended periods of time. Always keep the tank full to prevent rust is the best method.

 

Hey.. Nice job.. Gonna give that a go on some of the other parts I have that are rusted up.

I think the trick here is to make sure you DON'T switch on the car charger until after you are CERTAIN your electrode is NOT touching any of the sides.. (If it is, you're likely to burn a hole!)

 

take a meter check to make sure its not touching also if its touching the meter on the charger will peg and the safety should pop the charger off. if you use a low amp charger it shouldnt burn a hole anyhow. just make sure you have the termanals hooked up properly. if you hook them up backwards it will bont the rust to the tank instead of the anode

 

here is an article on how to do it

There is a simple way of forcing the rust to plate a sacrificial electrode (steel or iron), but the process can take quite some time. Needed are a battery charger (a weak one will do) or other power-source (an old step-down power brick for an discarded electrical device will work if you slap a couple alligator clips on the leads), a piece of bare mild steel or iron as large as you can find that will still fit through the gas-cap opening without touching anything, water and washing soda (Arm & Hammer brand will do nicely).

Remove the fuel-tank sender assembly, the petcock, the gas cap assembly, and any other removable items from the gas tank. Seal up all the holes in the tank except the gas cap filler hole (using plastic or rubber -- do not use aluminum), so that it's water-tight.

Mix 1 Tablespoon of washing soda per gallon of water and fill the tank with the mixture (note: stronger will not accelerate the process, so don't go overboard).

Without plugging it into the wall, connect the battery charger or other power source as follows: positive to the mild steel or iron part, and the ground to the gas tank itself (such as to a screw that normally holds in the petcock). You need to make sure that the lead to the mild steel or iron part will not touch the tank's metal, so insulated wiring is smart.

Figure out how to support the steel or iron part in the tank without touching the sides or bottom, and without forming a grounding circuit to the body of the tank (a bit of nylon mesh attached to a plastic ring too large to pass through the opening of the tank will work wonderfully -- or some nylon twine tied off to something above the tank). Lower the metal into the tank and double check that it's not touching anything except the solution.

Now you're ready to energize the system -- plug in the charger. How long the process will take will vary with three factors: the amount of surface area of the metal piece being suspended into the solution, the amount of power running through the solution, and how much rust we're dealing with here. In particularly bad cases, you may have to drain/rinse out the tank every 12 hours, wipe down the metal, then start over. If the mixture looks like a dark red stew, definitely time to change it. You will also need to top off the mixture with additional water if the level falls, as the process cooks off water (electrically rips it apart).

 

This technique also works wonders on small parts. I used electrolysis to remove the rust from my car's extremely frozen emergency brake lever after 4 days in PB Blaster did nothing.

 

I'm trying this method for my tank as well but can't seem to get it to work. I have a trickle charger that I was using, but I felt like the amperage might be too low, so I borrowed a friend's charger. Unfortunately, it's one of those "smart" chargers that won't work if it detects that it's hooked up incorrectly. So I hooked it to my car battery, then had leads coming from the battery terminals to the tank. Still, no real results, even after sitting overnight. I must be doing something wrong; it looks like it worked wonders for you.

 

First, I definitely would NOT connect a car battery for the power source. If you accidentally shorted out, you would have some serious safety issues. The high current from the battery would, if your lucky, only weld the leads to the tank.

The power source really should be a battery charger capable of putting out 10 amps. You also need it's built in safety circuit.

Do you have the polarity connected correctly?

 

First, I definitely would NOT connect a car battery for the power source. If you accidentally shorted out, you would have some serious safety issues. The high current from the battery would, if your lucky, only weld the leads to the tank.

The power source really should be a battery charger capable of putting out 10 amps. You also need it's built in safety circuit.

Do you have the polarity connected correctly?

 

I'm in the process of "electrocuting" my tank right now and I'm wondering about how long I should let it go. I've had it running on the 2 amp setting for close to three hours and there is definitely a lot of activity and junk collecting in the fuel cap hole (which is open).

Is there any value to emptying it part way through and adding a fresh water/sodium carbonate solution?

Is it possible to do any damage by letting it go too long?

Thanks!

 

Since I posted I've been searching the forum for info about how long people have let this process go. I'm just laughing now because I've read everything from 4 hours to 10 days with multiple rinses and anode scrapes.

Maybe I should start a poll...

 

I ran two tanks of solution to do mine. About 1 hour on each tank full did the trick with a 10 amp charger.