Electrolysis Rust Removal Fuel Tank RepairRemoving rust from parts seems to be something I need to do way too often. I came across this electrolysis rust removal method while researching the best way to remove rust from a motorcycle gas tank. I didn't want to purchase a gas tank sealer kit and found out as long as your tank isn't rusted through, there is no need to seal it. Electrolysis rust removal is really easy to do and kind of fun as well. Before I get into this rust removal techniqe, there is one very important thing you need to know.
- OK, here's what you need for elecrolysis rust removal
- Battery charger
- LAUNDRY soda (not baking soda)
- Tap water
- Sacrifical steel electrode (soft steel part that attracts the rust, remember NO Stainless Steel)
- Something to suspend the sacrifical electrode in the water (the electrode must not be touching the gas tank)
Exhibit A, the rusty gas tank from my old Harley Davidson Sportster. As you can see the metal inside the tank is rusted and dirty looking. This is typical of a gas tank that has sat for a while without fuel in it. I removed the petcock from the rusty fuel tank and plugged the hole with a rubber stopper.
I used this ibolt for my electrode since it was handy in the garage. Most bolts like this have a zinc coating, I sanded the zinc off the round end a bit with a scotch brite pad. When I do this again, I will use a longer piece of soft metal as the electrode, bend it such so it goes down inside along the side of the gas tank (without touching the tank), and then stop an switch it so to do each side of the tank for a while (remember line of sight).
I found this black plastic thing in the garage, it already had a hole in it and looked like it would work perfectly to hold the ibolt in the tank so I decided to use it. You can pretty much use anything that doesn't conduct electricity for this. We are removing rust from a gas tank, it doesn't have to be pretty :-)
I screwed a nut on the back of the ibolt just far enough so the ibolt will hang in the tank without touching the inside of the tank.
After filling the gas tank with warm water, I added approximately 1/4 cup of LAUNDRY soda. Just to recap, laundry soda is different from baking soda. You can find laundry soda at most grocery stores. More isn't better here, about a 1/4 cup will do just fine. Here I am lowering the sacrifical electrode into the soda water mixture. We're almost ready to start removing rust!
Remember POSITIVE on the electrode, NEGATIVE on you're part. Connect the terminals before you plug in the battery charger. I put the black tape on just to hold it in place. In no way do you want to seal the gas tank. do this in a well ventilated area and let the gasses escape out the top.
With the battery charger plugged in and set at 6 Amps, the rust removal process is drawing about 2 Amps here. I left it on for about 50 minutes on this first run. I would have left it longer but I had to go do something else and didn't want to leave it sit there unattended.
Look at the soup in the gas tank after just 50 minutes! I dumped out the muck in the tank and rinsed it out really good with water. Next I used a heat gun to blow inside the tank until it was dry. I finished by spraying WD40 all over inside the tank. After just a 50 minute run with this small electrode, the tank was quite a bit cleaner on the inside. Success!