Rusty -- a.k.a
RadioHowie One
Really Rusty
Howie Two
One of the better products (clickable pic)
POR-15
POR has a kit available that includes all the chemicals to clean, prep, and coat a tank. The most challenging part of PORing tank is the tedious drying process. After the cleaning and prepping, which adds a charge to the metal so the coating will adhere to it, the tank must be completely dried. If this step is not done correctly the entire process will fail. The most effective ways to dry a tank seem to be running a source of hot air through it, while setting it out in the sun. Once the tank is dry, the coating may be applied. Once dry, the tank will last for years without worry of rust(some user's have experienced 15+ years of no rust). POR is highly recommended above Kreem, as Kreem has a tendency to fail after time, while POR does not (when done properly).
Another popular fix, but not nearly as good as POR 15 (Clickable pic)
Kreem
Kreem is a commercial product for coating the inside of a tank with a chemical compound resistant to the corrosive effects of gasoline. It's a bit more difficult to use properly than is initially apparent. For one thing, it's extremely sticky and viscous. Also, it's hard to get an even, thin coat without cutting your tank in half. Overly thick coatings result in flaking, which will clog your petcock or filter, or, worse, destroy your carburetor jet etc. etc. However, when done proffesionally, it is effective for many years. For long lasting results, this product should be avoided.
A
third common kit
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A very good electrolysis process to de-rust the tank, it chemically heals the tank and prevents future rust.
You need
1 rusty gas tank
1 small container of sodium carbonate, chemical compound, Na2CO3 pool/spa supplies PH+
1 4amp or better battery charger
1 average bolt approx 3/8 x 1.5
1 short length of copper wire, ~ 12 awg
1 qt naptha
1 qt denatured alcohol
Empty out all the gas, take out the petcock and remove the fuel cap. Remove any old fuel residue and varnish with a good rinse of naptha to make it petroleum free, and then drain / dry. Using a sock with a handful of small nuts/washers etc, add a little water and shake this all around inside the gas tank to loosen the big chunks, rinse with clear water, scrub well. In a clean pail dissolve some of the sodium carbonate in water, 1/2 to 3/4 cup for a FJR tank, in a gallon of clear water, when its dissolved all the way stir it a bit more!
Seal up all but the filler cap opening on the top, pour in the well stirred mix using a funnel if you've had too much coffee. Fill the tank right to the top with water, set the tank so that the cap opening is the highest part, burp out as much air as possible and keep the tank full for the process.
Wrap a half dozen or so turns of the wire around the bolt to hold it secure, twist it tight so the bolt won't fall off. Attach the (-) lead of the batt charger to the outer shell of the tank, attach the (+) to the other end of the copper wire, suspend the bolt in the solution and turn on the battery charger to a fairly high rate, an amp or two flowing is good, then wait. Time to process is ~48 hours and it won't overdo itself.
The bolt gets nasty after a day, I cleaned mine now and again to remove the crud but not sure it helps. After a couple days, remove the leads, discard the bolt, save the wire, drain and rinse the tank well, drag out that sock and slosh it all around to remove any loose material. Rinse a few more times until the rinse water seems clean, shake well and then use a bit of the alcohol to fetch out the rest of the water.
Once the tank is dry, you're all set to put it back into service. More coating not required.
Science, maybe remove this junk The process by which rust forms is electrochemical in nature so this method employs a reverse current flow in an alkaline bath at a higher voltage to reverse the process at a quicker rate. There are actually two forms of rust: iron III oxide or red oxide (Fe2O3) and iron II, III oxide or black oxide (Fe3O4)(FeO). Black oxide is a smaller molecule. The electrolytic process converts red rust to black rust and in the process the black rust becomes weakly bonded to the base metal. The black rust that takes the place of the red rust can be easily wiped, washed, or brushed off leaving rust free base metal. Any pitting that has occurred will remain, this method will not repair damage, but the pits will be rust free.
This is an alkali process and not acid, so you don't have a lot of pits in the steel filled with stray hydrogen ions which would just love to start rusting immediately instead of a much less active coating of black oxide.
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Another electrolysis process, they are similar:
"Cleaned 2 tanks using the following method, and was shocked at the results. Plus it was a lot of fun. Everyone that saw it eventually did their tanks as well. Cost 50 cents for the salt, and a buck for the rebar I used.
Mix 1/2 canister (about 13 oz) of common table salt with 3 gallons of water.
Block the petcock and sending unit holes, then fill the tank right up to the filler neck so that all inside metal is covered with the salt water. Use fresh water to fill as needed. You will add extra salt later.
Make an electrode out of something steel (I used some 18" x 3/8" rebar I had laying around). This will go into tank, and must NOT touch anything metal in or on the tank. Use a plastic funnel at filler neck to prevent touching, and use a wad of tape at bottom of rod to prevent touching. Make sure tape goes up far enough so that tank hump does not touch rod.
Use a "manual" battery charger of at least 10 amps.
Connect negative cable clamp to rod.
Connect positive clamp to tank. I used the tank mounting bolt.
(flow is positive to negative, so rust will leave positive charged tank and go to negative charged rod).
Turn on the charger and adjust your charging rate to get as close to 9 or 10 amps as possible. Add more salt to increase charge. I had to use almost all of the canister to get near 9 or 10 amps draw on each tank.
You will see bubbles forming and the water will turn brown.
First tank was spotless in about an hour!
Jaws did drop! We expected something to happen, but nothing this good.
Second tanks was rough, and it took about 3 hours cooking before it too was spotless. This second tank was for a ninja, and the dealer told him tank was junk and could not be cleaned or used. WRONG! 6 months later it is still like new.
You can reuse the solution. Turn off charger, remove rod, empty tank, and look at results. Pour solution back in and restart process if needed. It's cheap enough to use a fresh batch each time.
Watch the rod. The second tank ate away the rod at one spot about 80% through. Change if needed.
I found this by searching various methods. Google and see similar methods. Most describe sodawash instead of salt, but it takes longer. Salt works!
No sealing of either tank was needed. Rust was removed, not metal. Where there was rust, there is now a darkened scar. When done, rinse dry and coat tank right away. Tank will start to rust again very fast. I used tranny fluid to coat tank.
WARNING: I think this creates a type of Chlorine gas, so don't stand above the tank, looking into it while cooking and breath the fumes. Be smart and use normal precautions. (well ventilated area outdoors, etc)."
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Battery and Washing Soda/Electrolysis
Remove rust and amaze your friends with Science! Electrolysis is a technique for returning surface rust to iron. The process actually alters the tank wall on the molecular level removing the oxygen that has oxidized (rusted) the tank. This method has advantages over old standbys like vinegar, Coke, muriatic acid, naval jelly, wire brushing, sand blasting, etc. because those methods all remove material to get rid of rust. These other methods also remove un-rusted material. The electrolytic method removes only the oxygen from the oxidized metal by returning surface rust to metallic iron, rust scale is loosened and can be easily removed. Un-rusted metal is not affected in any way.
What do you need to make this work? Not much, really:
* Your rusted gas tank.
* A battery charger or other source of 12V DC power.
* Wires or cables to connect the electrodes together, lLower guage better, less heat. make sure it insulated.
* Sacrificial electrodes - iron re-bar works great, stainless steel is very bad (and the result is illegal and dangerous). Go to your hardware store get some non coated steel
* Arm & Hammer LAUNDRY Soda, also known as washing soda.
* Some chains or steel wire to suspend the part in the solution - copper wire is bad and messy.
* Water
The basics are pretty simple.
1. Look in your tank. Get familiar with the inside of your tank you are going to need to fit the Sacrificial anodes in there and have them not touch the edge, because it will cause you to ground out and not work.
2. Mix 1 Tablespoon of Washing Soda with every gallon of water to create an Electrolyte solution. (Don't go overboard with the washing soda people. It won't help.)
3. Cut your sacrificial anodes to lengths that will fit in the tank. I drilled holes at the top to attach a wire. Now use electrical tape to tape the wired end and the other end thickly so there is no possible way you can ground out on the edge. You can use more then one at a time.
4. Wire all of the electrodes together so they are, electrically speaking, one big electrode. Make sure all connections are on clean metal and sufficiently tight to work.
5. Suspend your part in the solution using the wire/chains so it is not touching the bottom and is not touching any electrodes.
6. Attach the battery charger NEGATIVE lead to the part and the POSITIVE lead to the electrodes. Do not get this backwards! If you do, you'll use metal from your part to de-rust your electrodes instead of the other way around -the positive electrodes are sacrificial and will erode over time. That's how the water becomes iron-rich. THE POLARITY IS CRUCIAL!! The iron or stainless electrode is connected to the positive (red) terminal. The object being cleaned, to the negative(black). Submerge the object, making sure you have good contact, which can be difficult with heavily rusted objects. Get it backwards and your object will be relentlessly eaten away! Make connections on a part of your electrode that protrudes out of the solution, or your clamps will erode rapidly.
7. Double check everything to be sure the right things are touching, the wrong things are not touching, and the cables are hooked up correctly.
8. Turn on the power - plug in the charger and turn it on.
Within seconds you should see a large volume of tiny bubbles in the solution - these bubbles are oxygen and hydrogen (very flammable!). The rust and gunk will bubble up to the top and form a gunky layer there. More gunk will form on the electrodes - after some amount of use, they will need to be cleaned and/or replaced - the electrodes give up metal over time. That's why re-bar is such a nice choice - it's cheap and easy to get in pre-cut lengths.
The process is self-halting - when there is no more rust to remove, the reaction stops. This is handy because you don't have to monitor it, and because you can do large parts where they are not totally submersed at one time (aka, by rotating them and doing half at a time) without worrying about "lines" in the final part.
Once you are done, the part should immediately be final cleaned and painted - the part is very susceptible to surface rust after being removed from the solution. There will be a fine layer of black on the part that can be easily removed, and once it is removed, the part can be primed/painted as needed.
Safety Precautions
You're playing with serious stuff here, so stay safe. It's not rocket science, but if you're new to this, you might not know all of this - so read up before you do any of this.
* This process produces highly flammable and explosive hydrogen gas (remember the Hindenburg?), so do it outside, or in some other well ventilated area. Hydrogen is lighter than air (like natural gas), so it will collect near the ceiling - not sink to the floor like some other flammable vapors will (like propane and gasoline). If you have open flames near this (Hint: gas appliances like water heaters and furnaces have pilot lights!) you will most likely severely injure or kill yourself (and others near you) and become a contender for the Darwin Awards in the process.
* Assuming you used re-bar and steel wire/chain like you were told to, the waste water resulting from this is iron-rich - it's perfectly safe to pour it out onto the grass and your lawn will love it. Beware of ornamental shrubs that don't like iron-rich soil though, unless you like making your wife mad at you.
* Make sure the battery charger (or whatever source of power you use) stays dry. All of the usual cautions about any electrical device in a wet environment apply here.
* The solution is electrically "live" - it is a conductor in this system. Turn off the power before making adjustments or sticking your hands into the solution. You can get a mild shock if you stick your hands into the water with the power on.
* The solution is fairly alkaline and will irritate your skin and eyes. Use gloves and eye protection. Immediately wash off any part of your body the solution comes into contact with with plenty of fresh water.
* Don't use stainless steel for the electrodes. The results are toxic and illegal to dump out.
* Don't use copper for the electrodes and anything else in the water - the results are messy.
If you are unsure of any of this or unsure about your safety - STOP! Get help before you do something stupid. Use common sense, be smart about what you're doing, and stay safe so you can finish your restoration project and enjoy it.
