Rusty gas tank

I have a gas tank that is rusty on the inside and outside (no paint or primer). My last resort is to take it to a plating shop to have it dipped, but is there anything I can soak it in to remove the rust? Fill a big rub of CLR and watch it bubble?!?!? :laugh:

kzrider.com/forum/2-engine/469788-using-...t=20&start=20#482796

everyone seems to have a remedy mine is CLR some are vinager some are electrolisis or something like that you will even get cut it apart grind it and weld it back up but your time and money will best be spent in having it dipped, boiled out or whicever process the radiator or plating shop uses. I have tried a couple remedies with varying results from no change to a bazillion pinholes.

my next rusted tank will get dipped last I heard it was about 20 bucks. dipped and sealed about 50

learned my lesson after spending countless hours cleaning and custom paintwork only to watch my paint lift and tank develop new leaks due to pinholes that developed after my cleaning.

and the Kreem treatment was of no help it only allowed me a weekend of enjoyment. while the JB weld has held til this day, I have new leaks developing.

CLR 6.00
JB weld 4.00
Kreem 48.00
6 days of fooling with it
Paint supplies 300.00
48 hours of paint labor
Trust me if its very bad take it spend the money you will be glad you did

light surface rust on the inside CLR, Viniger, electro whatever
Light Rust on the outside Sandpaper, grinder, stripping wheel

Heavy rust SEND IT TO THE RADIATOR SHOP

my .02

My test piece, overnight soak.

This is what I used, 27 bucks and 3 days of turning the tank to get all surfaces inside.

I used red-kote on the inside of my tank and followed the instructions exactly. no problem so far but only been a month. Sorry haven't dealt with outside as I am lucky enough to have nice paint there.

www.damonq.com/TechSheets/Red-Kote.pdf

Oxalic Acid Rust Removal On Gas Tanks(Found On the internet at www.wgcarbs.com )

Just ordered a few pounds of it this morning, it "should" remove the rust in my Kaw tank and it's great for removing rust on shop tools or whatever too.

I used this stuff while I lived in Florida where the humidity usually averaged 100% and it saved me a lot of labor ... it's Eco friendly too. Our humidity here in Alabama is just about as bad as on the gulf coast ... so even if it won't completely clean the tank rust out ... and I truly believe it will ... I can make good use of it

Don't know why I didn't think about it sooner, mixes with tap water, flushes out easy, it won't harm paint, plastics, aluminum or anything of that nature ... just kills the rust and leaves the metal coated to help prevent future rusting.

The guy's name is Gregg and he has a ebay store but you can buy directly from him, send payment by check or paypal. I talked to him yesterday and told him there would probably be more folks from the forum inquiring about it. He said to have whoever calls or emails to remind him they're from the forum.

It sells for $4 a pound and he can fit 4 pounds into a flat rate priority mail package and ship it for $4.95. So 4 pounds should go along way since it can be used over and over again. $20.95 for 4 pounds shipped isn't bad at all in my opinion. The only way he's making any profit on it is by buying LARGE quantities and selling small.
I'm probably going to set up a large vat to soak tanks and tools in.
This stuff will eventually turn black after heavy use but it still cleans good and washes clean with tap water.
He claims he's had several people use it for cleaning rusty tanks with great results and I know I had good luck with it before too, just never used any on a tank ... but will soon.

Here's his info: Best to try his cell first.

Gregg MacEllven
Sea Shield Marine Products (sales rep)
Mac's Pacs; teak/mahog plugs, flax, oxalic, etc.
macspacs@sbcglobal.net
310-547-2687 (home)
310-547-2606 (fax)
310-721-9667 (cell)

Late yesterday afternoon I mixed up a batch and put it inside my original KZ tank.
The tank had what I would call a medium overall surface rust throughout the inside and a fairly heavy rust build up along the entire bottom surface.

The instructions suggest warm water but I talked with Gregg and he said it wouldn't really matter as long as I wasn't looking for INSTANT results and let it soak so I used unheated water from the hose and about 8 heaping tablespoons of Oxalic acid and let it soak for 24 hours.

I just drained the tank and the water was colored kind of a light brown, I flushed the tank with clean water twice and looked inside as far as I could see with a strong miniature LED flashlight and NO RUST was present ANYWHERE including the bottom surfaces.
The Oxalic acid left behind a off white colored protective coating on the metal surface just like Gregg said it would

Once I got the tank dry I saturated a shop rag with gas and rubbed the white coating with it and the coating stayed put.

But ... I will highly recommend you folks give this stuff a try because it sure takes the work out of removing rust from our gas tanks and it did not faze the paint either where I overfilled it.

This old tank will get repainted and used now that the rust is gone ... but for you folks that have internal surface rust on tanks that still have good paint on them, don't worry ... this is the ticket right here !

I can tell you right now that it works very well, the tanks I cleaned back in November have sat in my shop until I decided to tag & drive my 78 KZ a few days ago.

I looked at all 3 tanks & they still looked rust free inside other than a small haze which may be simply what the metal looks like after sitting so long after being treated. I thru a 1/2 gallon of gas in it, sloshed it around, poured it out, installed the tank with clear gas line & the fuel runs out CLEAN ... no rust deposit showing up in the filter either !

Oxalic acid WORKS better than anything I've ever tried in 30 years of wrenching. Use hot water, mix it up double or triple strength, fill the tank to the rim and let it sit overnight. If you don't get the results you want, do it again, this stuff is cheap and WILL clean the rust out of tanks without harming the paint even.

I kept several gallons of used mix in a large plastic container & constantly throw stuff in it like a set of rusted boat trailer wheels, impact sockets etc. & it cleans them like new, may take a while but it works.


Some tanks may require more acid to do the job but this stuff is cheap & easy to use, won't even burn the grass when poured out.

I did a Honda tank for a buddy that had some ridiculous rust along the inside bottom flat areas & top part of the hump. I tripled the recipe & let it sit a couple of days and it came out CLEAN.

Would rather NOT use a tank liner product that may or may not peel away ... oxolic axid won't hurt the paint either, so that's a huge plus.

MFolks wrote: Oxalic Acid Rust Removal On Gas Tanks(Found On the internet at www.wgcarbs.com )

Just ordered a few pounds of it this morning, it "should" remove the rust in my Kaw tank and it's great for removing rust on shop tools or whatever too.

I used this stuff while I lived in Florida where the humidity usually averaged 100% and it saved me a lot of labor ... it's Eco friendly too. Our humidity here in Alabama is just about as bad as on the gulf coast ... so even if it won't completely clean the tank rust out ... and I truly believe it will ... I can make good use of it

Don't know why I didn't think about it sooner, mixes with tap water, flushes out easy, it won't harm paint, plastics, aluminum or anything of that nature ... just kills the rust and leaves the metal coated to help prevent future rusting.

The guy's name is Gregg and he has a ebay store but you can buy directly from him, send payment by check or paypal. I talked to him yesterday and told him there would probably be more folks from the forum inquiring about it. He said to have whoever calls or emails to remind him they're from the forum.

It sells for $4 a pound and he can fit 4 pounds into a flat rate priority mail package and ship it for $4.95. So 4 pounds should go along way since it can be used over and over again. $20.95 for 4 pounds shipped isn't bad at all in my opinion. The only way he's making any profit on it is by buying LARGE quantities and selling small.
I'm probably going to set up a large vat to soak tanks and tools in.
This stuff will eventually turn black after heavy use but it still cleans good and washes clean with tap water.
He claims he's had several people use it for cleaning rusty tanks with great results and I know I had good luck with it before too, just never used any on a tank ... but will soon.

Here's his info: Best to try his cell first.

Gregg MacEllven
Sea Shield Marine Products (sales rep)
Mac's Pacs; teak/mahog plugs, flax, oxalic, etc.
macspacs@sbcglobal.net
310-547-2687 (home)
310-547-2606 (fax)
310-721-9667 (cell)

Late yesterday afternoon I mixed up a batch and put it inside my original KZ tank.
The tank had what I would call a medium overall surface rust throughout the inside and a fairly heavy rust build up along the entire bottom surface.

The instructions suggest warm water but I talked with Gregg and he said it wouldn't really matter as long as I wasn't looking for INSTANT results and let it soak so I used unheated water from the hose and about 8 heaping tablespoons of Oxalic acid and let it soak for 24 hours.

I just drained the tank and the water was colored kind of a light brown, I flushed the tank with clean water twice and looked inside as far as I could see with a strong miniature LED flashlight and NO RUST was present ANYWHERE including the bottom surfaces.
The Oxalic acid left behind a off white colored protective coating on the metal surface just like Gregg said it would

Once I got the tank dry I saturated a shop rag with gas and rubbed the white coating with it and the coating stayed put.

But ... I will highly recommend you folks give this stuff a try because it sure takes the work out of removing rust from our gas tanks and it did not faze the paint either where I overfilled it.

This old tank will get repainted and used now that the rust is gone ... but for you folks that have internal surface rust on tanks that still have good paint on them, don't worry ... this is the ticket right here !

I can tell you right now that it works very well, the tanks I cleaned back in November have sat in my shop until I decided to tag & drive my 78 KZ a few days ago.

I looked at all 3 tanks & they still looked rust free inside other than a small haze which may be simply what the metal looks like after sitting so long after being treated. I thru a 1/2 gallon of gas in it, sloshed it around, poured it out, installed the tank with clear gas line & the fuel runs out CLEAN ... no rust deposit showing up in the filter either !

Oxalic acid WORKS better than anything I've ever tried in 30 years of wrenching. Use hot water, mix it up double or triple strength, fill the tank to the rim and let it sit overnight. If you don't get the results you want, do it again, this stuff is cheap and WILL clean the rust out of tanks without harming the paint even.

I kept several gallons of used mix in a large plastic container & constantly throw stuff in it like a set of rusted boat trailer wheels, impact sockets etc. & it cleans them like new, may take a while but it works.


Some tanks may require more acid to do the job but this stuff is cheap & easy to use, won't even burn the grass when poured out.

I did a Honda tank for a buddy that had some ridiculous rust along the inside bottom flat areas & top part of the hump. I tripled the recipe & let it sit a couple of days and it came out CLEAN.

Would rather NOT use a tank liner product that may or may not peel away ... oxolic axid won't hurt the paint either, so that's a huge plus.

do not use oxalic acid it does not work, been there done that, IF U DONT GET IT ALL OUT, WHICH IS A PAIN IT REACTS WITH ETHANOL :S :S :S

and NEVER USE KREEM

HOLY CRAPPY KREEM APP! :laugh:

OK - rust inside and out... hmmm... sure its not right through?
Take the rust off the outside of the tank with sandpaper/wire wheel/whatever.
Place folded towel over the spots that had rust and give them a moderate tapping with a ballpeen hammer. Note enough to dent the tank - just enough to determine the metal is ok/still substantial enough.

If tank is good to go...

Method 1: my fav.
rinse the tank out several times with water.
Flip over.
Roto zip the bottom plate off the tank (cut in two halves - top/bottom) about 1 inch in from the sides - very easy to do.
Remove all teh internal rust by hand sanding/wire wheel... then wash and dry thoroughly.
Take tank when done to have it welded back shut - TADA! - LIKE NEW TANK.

Method 2: easy cheesy.
rinse tank several times with water.
Add a length of heavy steel chain to the inside of the tank and seal off the openings.
Put the tank in a plastic garbage bag, then wrap it in a gigantic comforter/blanket and throw it in everyones favorite homade tumbler (THE DRYER).
Stuff pillows in there around it to make sure it is stabalized in the center of teh dryer.
Select the longest timed cold tumble and forget it.
When done - all that rust inside is pretty much pulverized and will just rinse out.
May have to do it a couple times - splash some motor oil around inside when done to nuetralize any remaining rust spots and prevent flash rusting.

Remember, always check your fuel filter periodically throughout the year for blockages!

Good luck.

I 'Kreemed" my 75Z1B tankk about 12 years ago and I have no issues, beeing peeling, flaking, etc with it.
Like with a paint job, preparation is the key to sucess. ( as well than following the instruction to the letter)
Obviously in the picture you can see rust on the back side of the kreem as well than on the metal.
Poor prep, nothing more.

www.kzrider.com/forum/6-paint-a-bodywork...ning-rusty-fuel-tank

This worked well for me. Thought I had replied to this thread. It's simple, works well. Not sure about the exterior of the tank, but this will help with the interior.

mtbspeedfreak wrote: I have a gas tank that is rusty on the inside and outside (no paint or primer). My last resort is to take it to a plating shop to have it dipped, but is there anything I can soak it in to remove the rust? Fill a big rub of CLR and watch it bubble?!?!? :laugh:

I can only comment on the inside, haven't had to resto a tank's exterior yet.. but done a bunch of the insides. Once the tank's inside has been cleaned and sealed, however, you can utilize standard autobody resurfacing and painting techniques for that part. I have a simple process for the inside:

Materials:
1. "Ospho" available from hardware stores like Ace.
2. Caswell Plating Company gas tank sealer kit.

Ospho
Fuel Tank Sealer

Process:
The inside of this KZ1100 tank I did was about a 3-4 on a scale of 1-10, it took three applications of Ospho to clean it out. Seal up the holes (I make aluminum plates and gaskets from scratch to do this) by bolting these plates to their locations with the OE bolts. Put like a third of a 1/2 gallon of Ospho (you can get it by the gallon too), slosh it around, wait awhile, maybe 15 mins, dump it, let the residual just dry up. A white scale will appear on the metal. That's good. Next day or two, do it again, repeat as many times as needed but on the last time, rinse with A LOT of water. Dry it fast. I have a drying rig I made with a big rubber hose and an old hair dryer. I get it dry fast so it won't flash rust much, if any. I DO NOT spray anything like WD40 or similar because it'll foul up the sealing part.

Mix up the fuel tank sealer kit and dump it in, with the plates that cover the holes attached. Now, this is the tricky part: you have to swirl that stuff around a lot, but even afterwards, as this stuff kicks, you have to turn those bolts or screws that the plates are attached with, or the epoxy will pretty much weld them in... not good. Turning them once in a while ensures they'll come out.

Let cure a couple days, then go to town on the outside.

I've used this stuff quite a few times, it's a great product from Caswell. About $55 with shipping for the kit that will do up to a 5 gallon MC tank.