Author Topic: Electrolytic Rust Removal From A Motorcycle Gas Tank.... anyone see this?  (Read 16811 times)

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Offline xsmooth69x

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Offline HondaMan

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http://www.instructables.com/id/Electrolytic-Rust-Removal-From-A-Motorcycle-Gas-Ta/#step1

looks cool i wonder if it works?
I used salt instead of baking soda: it worked fine. Maybe the baking soda is less aggressive than salt?
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Offline Dyrden

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Ive done it.  Works like a charm.  Science instead of elbow grease!

Offline xsmooth69x

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if i took a huge pool of water and B powder can i just drop in carbs and petcocks and exhausts in it?
1975 CB550 (FINISHED?!?!?)
first motorcycle ever!!! ow and i dont know how to ride it either :D

raw rust rice venti quad shot cafe racing latte project aka my build..... http://forums.sohc4.net/index.php?topic=88853.0

black and white equation godzilla chalkboard 
1972 cb750 - next in line for some <3

Offline Dyrden

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if i took a huge pool of water and B powder can i just drop in carbs and petcocks and exhausts in it?

Yes.  However it works on "line of site" so things not exposed to the sacrificial steel will still have rust.  Youll need to move things around a bit.  I used a 12v batter charger and let it sit for a day.

Offline xsmooth69x

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what if i use a cookie drying rack?
1975 CB550 (FINISHED?!?!?)
first motorcycle ever!!! ow and i dont know how to ride it either :D

raw rust rice venti quad shot cafe racing latte project aka my build..... http://forums.sohc4.net/index.php?topic=88853.0

black and white equation godzilla chalkboard 
1972 cb750 - next in line for some <3

Offline Dyrden

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what if i use a cookie drying rack?

Your wife won't appreciate it. And it's such thin gauge a probably coated with somthing so I don't think it's the best solution. I used a 1 foot piece of angle iron.

Offline Radam

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A friend of mine used a big plastic outdoor storage tub and made a cage out of rebar around the edge of it and it worked great.

Offline Dyrden

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I used a plastic trashcan from homedepot on sale for like 8 dollars.

Offline zackblack

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I did it to my tank and it only sorta cleaned it...
:) If I ask a question and forget to post model and year my bike is a '72 CB500 :)

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Offline sopo400f

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I just did the molasses treatment for my tank and it worked great! Safe on paint and cheap.
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Offline BobbyR

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This has been posted here before. If you do a search you can find a how to with pictures.
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline nancy

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I used this technique on my gas tank 16 months ago with great success and used it recently to de-rust the inside of my front wheel rim, prior to re-chroming and new spokes. I used a large polystyrene fish bin full of water with about a pint jug of salt. Used a 3 foot length of steel pipe as a sacrifical anode. Put the wheel in (without tyre of course) and left it for 4-6 hours and rotated till all the wheel received equal treatment - left it for about 4 days total. Produced enough brown foam to fill an olympic pool - what a mess! Rim came out really nice. Finished with a linishing by the electroplater.
I see no reason why this would not work on a carb rack. Consider removal of everything non-metallic...seals etc.
Mark

Offline BeSeeingYou

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Why would you use this on carbs and petcocks?  It will not clean gas residue,varnish, grease, etc.  It is used to remove corrosion from steel.  I would be careful about putting mixtures of metal together in an electrolyte.  Your carb has aluminum, brass, maybe stainless or plated steel?  Research galvanic corrosion.

I have used this on gas tanks.
« Last Edit: June 28, 2011, 12:27:01 AM by srust58 »

Offline zackblack

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On the contrary - when I did this to my tank it did clean the gas residue, varnish, grease, etc from it...

...it just didn't get it all and (not even a third of the rust) and it took a LONG time.
:) If I ask a question and forget to post model and year my bike is a '72 CB500 :)

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"Observe the snow. It fornicates."

Offline tango911

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I bought a 5 gallon bucket of "metal rescue"  for $80 and cleaned 6 tanks with it.  You can re use it till it turns black.  that came out to $13 per tank to clean.   Its also safe for the environment.  I fill the tank over half way, let ti sit for 12 hours, then shake it up  and turn it over for another 12 hours.
I would like to try the electrolytic way sometime.
just another option
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Offline Johnie

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I did the same as tango and used an environmentally safe rust remover which did a great job. Price was the same as tangos, but again I can re-use it numerous times. Came out of NY. Here is the website http://www.safestrustremover.com/ if you want to give it a try. I like that fact I don't have to worry about breathing it, won't hurt paint, won't burn hands and there is no flash rust. No need to line it either. Here is a before and after pic. Click to enlarge it...
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Offline splitt

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Another product for rust removal is called Rustbeeters:

http://rustbeeter.com/

It's a green product made from sugar beets. It's made for removing rust from steel an cast iron. You cannot do aluminum with it though.

Offline BobbyR

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Here is a link on the electrolysis method. While he built his own power supply, a car charger will do the same thing.  http://www.landyzone.co.uk/lz/f38/rust-removal-using-electrolysis-63065.html
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline Radam

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I just pulled apart a tank from a 81 Kawasaki 440 and I'm thinking about using the electrolysis method or sand blasting. This is my first attempt at fixing a tank, so the tank is just a piece of crap that came off a bike that got totally submerged in a basement flood. I won't be loosing anything if I F it up.
How it started



After taking it apart at the seam with a 4" grinder

After a quick round of rubber mallet


I still have lots to do, but it's a start!
 

Offline gnarlycharlie4u

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http://www.instructables.com/id/Electrolytic-Rust-Removal-From-A-Motorcycle-Gas-Ta/#step1

looks cool i wonder if it works?
I used salt instead of baking soda: it worked fine. Maybe the baking soda is less aggressive than salt?

salt can make it flash rust faster.

I've used electrolysis with varying degrees of success. It usually works pretty well as long as you're doing it to things are a single piece.
Multi-piece components don't work too well.

here's a PDF of a thread from somethingawful.com on the subject of electrolysis from a couple years or so back:


Couple things to remember:
1) don't use stainless steel, the chemical reaction will result in chromium being released into your water. it is highly toxic and illegal to dump.
2) WASHING SODA (sodium carbonate, NA2CO3) is what you're supposed to use. not baking soda (sodium bicarbonate).
3) the closer together you put your annode and cathode the less resistance between them and the faster the process works. (DON'T LET THEM TOUCH THOUGH!)
4) Electrolysis produces Hydrogen which is highly explosive. do this in a well ventilated area and away from open flame.

also, in that thread he had the (-)negative terminal attached to the tank where it was painted. attaching it to bare metal will yield better results.

Offline WarwickE36

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+1 to Charlie

Quote
4) Electrolysis produces Hydrogen which is highly explosive. do this in a well ventilated area and away from open flame.
So if you're one of those MPG crazed "red green" mr. duct tape fix it types, put a top on the electrolysis bin and route a hose to the intake on your bike/car ... you can clean metal and get 150mpgs all at the same time.... and remember if the women don't find your handsome at least they'll find you handy
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Offline gnarlycharlie4u

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+1 to Charlie

Quote
4) Electrolysis produces Hydrogen which is highly explosive. do this in a well ventilated area and away from open flame.
So if you're one of those MPG crazed "red green" mr. duct tape fix it types, put a top on the electrolysis bin and route a hose to the intake on your bike/car ... you can clean metal and get 150mpgs all at the same time.... and remember if the women don't find your handsome at least they'll find you handy

i prefer hose to a waterbottle. then toss the bottles in a fire :D

Offline Terry in Australia

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I'm currently de-rusting the tank for my K6 project, it's a beautiful dent free OEM Valley Green (?) K4 tank but sadly, inside there's more rust than steel.

I used the tank cleaner from my POR15 kit but that hardly put a dent in the huge amount of rust inside it, so I thought "nothing ventured, nothing gained", so I used an old engine mount bolt (the long one) as the anode, filled my tank with a washing soda mix, and hooked up my crappy little 2.5 amp battery charger.

Now being that most articles here and on the interweb talk about using 8+ amp chargers (in contradiction to the linked article above, surprisingly) I wasn't expecting much, so I was pleasantly surprised with the large amount of rust I witnessed hanging off the anode only a couple of hours later!

Don't get me wrong, I'm only just noticing clean metal inside the tank now (on the anode side of the "hump" mostly) after 5 days of electrolysys so I might well need a bigger charger, (actually I bought a 16 amp charger on EBay but it's one of those stupid automatic "smart" chargers and it won't work on my electrolysys rig at all, so I wasted 105 bucks, bugger it...........) but regardless, it's producing a better result than the acid did. Cheers, Terry.  ;D   
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Offline xsmooth69x

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I'm currently de-rusting the tank for my K6 project, it's a beautiful dent free OEM Valley Green (?) K4 tank but sadly, inside there's more rust than steel.

I used the tank cleaner from my POR15 kit but that hardly put a dent in the huge amount of rust inside it, so I thought "nothing ventured, nothing gained", so I used an old engine mount bolt (the long one) as the anode, filled my tank with a washing soda mix, and hooked up my crappy little 2.5 amp battery charger.

Now being that most articles here and on the interweb talk about using 8+ amp chargers (in contradiction to the linked article above, surprisingly) I wasn't expecting much, so I was pleasantly surprised with the large amount of rust I witnessed hanging off the anode only a couple of hours later!

Don't get me wrong, I'm only just noticing clean metal inside the tank now (on the anode side of the "hump" mostly) after 5 days of electrolysys so I might well need a bigger charger, (actually I bought a 16 amp charger on EBay but it's one of those stupid automatic "smart" chargers and it won't work on my electrolysys rig at all, so I wasted 105 bucks, bugger it...........) but regardless, it's producing a better result than the acid did. Cheers, Terry.  ;D

you should try that eco green stuff posted above^^^

and are you cleaning off or replacing the your sacrificial anode when it gets all gross?

i would love to see pics  ;D

i cant believe this thread got so big
1975 CB550 (FINISHED?!?!?)
first motorcycle ever!!! ow and i dont know how to ride it either :D

raw rust rice venti quad shot cafe racing latte project aka my build..... http://forums.sohc4.net/index.php?topic=88853.0

black and white equation godzilla chalkboard 
1972 cb750 - next in line for some <3

Offline johnrdupree

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I wanted to learn how this worked so I did a test with an old saw I had laying around.  Pics of the process:

I bought a sheet of steel at Lowe's and cut it up into sections that would fit in a plastic bucket.  Also shown is the washing soda I used.  I can't remember what the concentration was, 1/4 cup per gallon of water, maybe, but it isn't exactly critical.  You just want to reduce the resistance of the water.



The anode in the bucket.  I was trying to get it set up so there would be no "blind spot."  If I had used only the section in the back and not the sides, only the rust surface facing it would have been cleaned.  The side facing away would have remained rusty.



The test piece.  I cleaned it with soap and a stainless brush to get the sap and goop off before the electrolysis.



The setup.  Saw in the water, not touching the anode.  Negative lead on the saw, positive on the anode.



Another view.  I had to keep the saw away from the anode, hence the piece of wood.



Making hydrogen.  This is after a couple of minutes.  I let it go for about a day and at the end the surface of the water was covered with rusty, brown scum.



The result.  When the saw came out of the water it was covered in a black film.  Warm water, soap, and a stainless brush gets rid of it and you're left with bare metal.



It works, it's cheap, and it can clean large areas of heavily rusted, oddly shaped items while you do something else, like clean carbs or paint your swimgarm.  It is a line of sight process so setup is important but not hyper critical.  The inside of a tank might be tough to do because you need to make sure the anode can see the entire inside of the tank but not touch anything.

Keep in mind, though, that like all rust removal processes it will not fill in pits in the base metal.  Once the rust eats away the original surface, that surface is gone forever and, if necessary, will have to be replaced by bondo, lead, welding, whatever.  Between this, oxalic acid, and naval jelly you should be able to de-rust just about anything a scabby old bike throws at you.

Good Luck,
~john
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Offline xsmooth69x

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so other than being cheap if you already have a battery charger is this a good way of doing the de rusting? i never heard of half the products just listed above or never worked with it.

is it as good as the electro?
1975 CB550 (FINISHED?!?!?)
first motorcycle ever!!! ow and i dont know how to ride it either :D

raw rust rice venti quad shot cafe racing latte project aka my build..... http://forums.sohc4.net/index.php?topic=88853.0

black and white equation godzilla chalkboard 
1972 cb750 - next in line for some <3

Offline Dyrden

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I suspended the anode(rebar) from fishing line rigged above my tank which was submerged in a plastic trashcan.  I lined it up so it went through the opening for the fuel injecting pump.  Worked like a charm.  I then put the tank in my oven on low to dry it quickly.

Offline BobbyR

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I'm currently de-rusting the tank for my K6 project, it's a beautiful dent free OEM Valley Green (?) K4 tank but sadly, inside there's more rust than steel.

I used the tank cleaner from my POR15 kit but that hardly put a dent in the huge amount of rust inside it, so I thought "nothing ventured, nothing gained", so I used an old engine mount bolt (the long one) as the anode, filled my tank with a washing soda mix, and hooked up my crappy little 2.5 amp battery charger.

Now being that most articles here and on the interweb talk about using 8+ amp chargers (in contradiction to the linked article above, surprisingly) I wasn't expecting much, so I was pleasantly surprised with the large amount of rust I witnessed hanging off the anode only a couple of hours later!

Don't get me wrong, I'm only just noticing clean metal inside the tank now (on the anode side of the "hump" mostly) after 5 days of electrolysys so I might well need a bigger charger, (actually I bought a 16 amp charger on EBay but it's one of those stupid automatic "smart" chargers and it won't work on my electrolysys rig at all, so I wasted 105 bucks, bugger it...........) but regardless, it's producing a better result than the acid did. Cheers, Terry.  ;D

Save your money Mate and hook it to a car battery.
Dedicated to Sgt. Howard Bruckner 1950 - 1969. KIA LONG KHANH.

But we were boys, and boys will be boys, and so they will. To us, everything was dangerous, but what of that? Had we not been made to live forever?

Offline Lostboy Steve

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is that dog ok? I like this a lot. I just recently (last week) used the por15 system for the second time. I had a tank that sat with gas in it since 1991. I had a little acid (metal ready) left over from a previous tank, so i threw it in and rolled the tank around every few hours for 3 days (nevermind the directions on the label). After that i did all the things the instructions say to do. I even boiled water to mix with the marine clean for the wash phase. This tank came out looking brand new inside. I would have loved to use this system though, looks simple enough. Also looks less time consuming than my 4 day method. The carbs also had all that goodness in them, so i sank them in lacquer thinner for 2 days and then boiled all the parts in vinegar once I was able to disassemble. All in all my way worked but I would have loved to save some time.
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Offline gnarlycharlie4u

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Here is a link on the electrolysis method. While he built his own power supply, a car charger will do the same thing.  http://www.landyzone.co.uk/lz/f38/rust-removal-using-electrolysis-63065.html

HAHA YES!!!

This is the same thread I read when I learned how to do it!

I just started a  fresh electrolysis run on my goldwing tank.
Here's some pics:

http://gnarlywrench.blogspot.com/2011/07/gl1000-gas-tank-removal.html

Offline Terry in Australia

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Save your money Mate and hook it to a car battery.

Thanks Bobby, I did think about just hooking up my jump starter pack thingy to it, and I still may. I've been away for a couple of days and while I was out in the country I drove by a chemical supplier, so I bought a 5 liter bottle of milking machine cleaner, that has 1100 grams of Phosphoric acid per liter (strongest one they sell) so I took it home, diconnected my battery charger, (there was a heap more rust hanging off the anode) dumped the electrolytic solution out (the tank looked cleaner inside, but still lots of rust) and refilled it with the acid and around 13 litres of water, put the tank inside a big plastic tub and left it overnight.

Good thing I put it in the tub too, because this morning there was more acid mix in the tub than in the tank. I'd forgotten that when I did the electrolysis process I'd sealed the petcock hole (and a couple of pinholes in the bottom) with aluminum tape, and it had obviously eaten thru the aluminum. Tonight after work I'll dump the remainder of the acid mix out and see how the inside looks, this tank is really rusty so will certainly need some repairs, but it's a dent free OEM paint tank that I could almost use (I say almost because there are a couple of surface rust spots on top too, sadly) without repainting, and I've never owned a green CB750.

If it's almost clean, I may try the electrolysis again, even though my setup with my pisssy little 2.5 amp charger is as slow as a wet week in winter, I can't do much until some more parts arrive, so I've got plenty of time. Cheers, Terry. ;D
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So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

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Offline stampederunner

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I had excellent results using rebar, a aresol carb cleaner cap and a small piece of rubber hose. I bent a piece of rebar in a "L" shape to fit in the tank cap and extend the length of the tank. Put a piece of rubber hose on the end of the rebar so it doesn't touch the tank. Then I poked a hole in the center of the aresol can cap to support the rebar and to keep it from touching the tank I also drilled multiple vent holes in the cap. I used a small piece of bicycle tube and duct tape to seal the petcock. Filled with water and washing soda and hooked it up to my battery charger set at 12v for only 5 or 6 hours.

Like others have said it is a line of sight procsess so I think the rebar extending into the tank is critical.
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Offline johnrdupree

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I had excellent results using rebar, a aresol carb cleaner cap and a small piece of rubber hose. I bent a piece of rebar in a "L" shape to fit in the tank cap and extend the length of the tank. Put a piece of rubber hose on the end of the rebar so it doesn't touch the tank. Then I poked a hole in the center of the aresol can cap to support the rebar and to keep it from touching the tank I also drilled multiple vent holes in the cap. I used a small piece of bicycle tube and duct tape to seal the petcock. Filled with water and washing soda and hooked it up to my battery charger set at 12v for only 5 or 6 hours.

Like others have said it is a line of sight procsess so I think the rebar extending into the tank is critical.

That sounds like a fantastic method.  All I would be concerned with is the tunnel casting a "shadow" onto part of the tank bottom, but that should be easy enough to work around.  For those who are going to try this, keep in mind that the surface area of the anode is part of what determines how quickly this works.  Even with rebar running the length of the tank it will have way less surface area than the inside of the tank.  It will eventually get it done, though.

stampederunner, how did you deal with the black residue after the electrolysis was finished?

~john
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1991 Honda ST1100
1989 Suzuki GS500E
1954 NSU Lambretta 125 (long term project)

Offline bender01

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I have done it with rebar,salt water and a battery charger. I did mess up and touch the inside of the tank. It was tack size hole quick. But it was clean!
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Offline Terry in Australia

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Well I dumped the phosphoric acid out of the tank and the tub last night, and it's working well. The vast majority of the rust is gone, but there are a few more pin holes than I'd hoped for, including one on top of the tank, about half way between the seat and the filler cap.

I refilled it with acid overnight and once I get back home tomorrow night (Army Reserve training this weekend) I'll give it a final wash out before I seal it with POR-15. I'm keen to try the electrolysis method again on another rusty tank I've got that's not as bad as this one, but I think the amount of rust in this tank was too much for my little 2.5 amp battery charger set up. Cheers, Terry.  ;D 
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)