Topic: Fuel tank went from a nice metal sheen to a rusted disaster!

[Dave-and-his-550]

I got a 1976 550F project I'm working on. I cleaned out my fuel tank the other day, and I used 'The Works' toilet cleaner in it like recommended. After I was done I had a nice clean metal finish, I was very satisfied. I let it air dry over night and well, look at the photo!! Its a rusted out disaster!

This is the order I did it in:

Filled with nails to break up any rust.
Got all the nails out and Washed it out with water
Poured 'The Works' in and let it sit for 10-15 mintues.
Washed it out (with water)
Poured some more Works in there and washed it out, at this point it was looking very good, and clean...


And here is where the first dilemma started: I then poured Acetone in like recommended BUT it got rusty right away. SO I decided to use The Works again, and it fixed it right up. After I got as much out as I could, I rinsed it with some fuel, and let it dry out over night...

Now look where I am! So, I know I messed up somewhere.

Also a note, it did begin to rain last night, and its been raining all day, so maybe the heavy moisture did it?  I don't know what to do now! Should I use 'The Works' again or should I use Evaporust?? Do I let it air dry or do I seal it up? Help!

[kghost]

Looks like flash rust.

Most of the fuel tank sealers...kreem, por15, etc recommend sealing the tank immediately after the treatment.

If your not gonna seal it add gas immediately.

I'd be tempted to add marvel mystery oil or some type of oil to the bare tank with the fuel.

Just my .02 cents

[FunJimmy]

WD-40 will penetrate the water layer and provide a protective coating on the metal.
After you do another clean and rinse, spray the entire inside of the tank with WD-40 and swish around to ensure complete coverage. If your wife is out of the house you could turn the oven to 150 degrees and after a through water rinse, warm the tank in the oven to dry. Watch it carefully to ensure the paint doesn't get damaged.

[Dave-and-his-550]

Ya, I completely forgot to seal it! Damn. Well, I got Evapo-rust in there now, hoping it will be clear by tomorrow, the fuel cap ring is really rusty also, I'll hit that with 'The Works' then to seal it I use WD40 or Marvel Mystery Oil? I'll give it a try...

Oh, and don't worry about the finish on my tank...There really ISNT one 

[kghost]

Por15 or Kreem are sealers.

WD40 is not a bad rust inhibitor..same for mystery oil.

[Hope]

Go with POR15.  Seems that everyone discourages the use of Kreem here.

Plus, I have Kreemed a tank, and just yesterday I POR15'ed a tank.  Seems the POR15 process was much easier.  Follow the instructions to a T.


I am surprised kghost recommended or even mentioned Kreem to you   

Well guys you may debate Kreem all you like.

I am going with the results I have seen over the last 15 yrs.

I cannot count the tanks that have been Kreemed where the liner has failed.

In fact I have yet to see a Kreem liner with any age still be attached to the tank.

It doesn't really matter if its milky, big chunks or pea soup. If its delaminated from the tank it isn't doing its job now is it?

I cannot comment what specific chemical added these days does the Kreem in.

One would have to have a sample of all gas ever put in the tank...plus a degree in chemistry.

I do know that we're talking about a produce (Kreem) thats been around virtually unchanged for a long time.

I theorize that the gasoline produced today is different substantially than gas 30 yrs ago.

Ferox, many of the peroxides, alcohols, Ethylenediamine's,  a virtual witches brew is added to modern gasoline.

Anyone know of any tests of Kreem with modern additives?

Forget the Kreem.  Go with POR15.  You can get POR15 here

Good luck

[eurban]

Doesn't phosphoric acid leave a rust inhibiting coating behind after it does its etching / rusting eating?  If so, you could do a wash with a phosphoric acid mix.  The Home Depot is now carrying it in the paint department.

[Patrick]

Any kind of acid bath can leave steel susceptible to flash rust. I acid bathe not only to clean tanks, but also to prepare metal for powder coating. I've had some luck neutralizing acid with laundry detergent. Laundry detergent is a base, which neutralizes the acid, but also a detergent that helps to remove any remaining film. Acid bathe the tank, rinse it with water, then pour a strong mixture of laundry detergent and water into the tank. Fill to the top and then let it sit for 30 or 40 minutes. Swish it around to get into the recessed areas. Drain the detergent, then rinse the tank a couple of times with fresh water and dry with compressed air.

This method was taught to me by a guy at the local radiator shop. I usually don't have to coat the tank with anything and the rust does not return. I've left tanks dry and empty for weeks after treatment and they remained clean. It also leaves parts real clean for powder coat.

Try it.

Patrick

[kghost]

Mentioned Kreem as an example only

[Hope]

Mentioned Kreem as an example only

figured this much.  POR15 is the way to go.  Seemed a lot easier that Kreem, too.

[seaweb11]

After the cleaning I have filled tanks with diesel for a day or so, then drain and flushed with fuel, then fill with fuel.

[hapsh]

You definitely can't use acid on metal and leave it bare overnight, especially in a rainy environment with high humidity.  When I used The Works, I had to pour marvels mystery oil mixed with a little gas right away after the acetone rinses.  As soon as I poured the last of the acitone out I put the gas/oil mix in immediately.  I sloshed it around really well.  I then just filled it with gas and started using the bike every day.  No rust at all in over 2 months.  If you do another shot of The Works, you might try diluting it first.  You probably just have surface rust that does not need really strong full strength to remove.  You don't want to start eating holes in the tank from too much acid.

[Dave-and-his-550]

Failed again!! Man, I am new to this...It got rusty again, I used the works, and then I rinsed it out with warm water. After I let it dry I put a bottle of Marvels in there and swished it around, then added some fuel. But not much because I don't wanna be sitting around with a FULL gas tank for a cycle that prob wont even start...

So I think where I went wrong, was not using a laundry detergent, or baking soda to neutralize the acidity of the Works first, before I used Marvels...

So what kind of detergent should I buy, would Borax have the same effect? Thats what I use at home for my laundry.

Should I use a mixture of acetone, baking soda, laundry detergent AND borax just to play it safe? (just kidding)

[Bob Wessner]

What kind of acid is in The Works? Is it hydrochloric? Use something with phosphoric acid, it leaves behind a gray oxide coating on the bare metal.

[Roach Carver]

What kind of acid is in The Works? Is it hydrochloric? Use something with phosphoric acid, it leaves behind a gray oxide coating on the bare metal.

+1

as has already been said there are many acids that will remove the rust. The trick is to get one that leaves an inhibitive layer on the metal surface to retard this flash rust (phosphoric acid). The acid in the works leaves the surface primed for rust. Not saying the works cant work, but phosphoric acid is the way to go.

[Patrick]

I'm not as patient as y'all. I used muriatic acid (50 percent solution) and laundry detergent. The muriatic acid erases the rust like you were rinsing dust off the metal with water. It only takes a very short period of time. It does, however, leave the steel extremely susceptible to flash rust. Not to mention what it quickly does to paint. That's where the laundry detergent comes in as a cleanser/neutralizer. I've had good luck with this method.

Patrick

[Dave-and-his-550]

So, where can I get phosphoric acid in a concentrate form? I don't think Diet Coke is a good choice at the moment...

Any other cleaning products out there that contain a good amount of phosphoric acid?

Only places I have to look are Tractor Supply, Oreilly Auto Parts, Super Walmart and Menards.

[Patrick]

Home Depot or Lowes. Paint department.

[Roach Carver]

some one said tractor supply has it now.

[hapsh]

Failed again!! Man, I am new to this...It got rusty again, I used the works, and then I rinsed it out with warm water. After I let it dry I put a bottle of Marvels in there and swished it around, then added some fuel. But not much because I don't wanna be sitting around with a FULL gas tank for a cycle that prob wont even start..

Did you use acetone after the rinses with water?  The acetone is VERY important, it absorbs the water that HAS to be removed before oiling.  I rinsed my tank 3 times so that there was no more acid in the tank and then poured about 2 cups of acetone in the tank and swished it around, dumped it out and repeated 2 more times.  That way I knew no more water was left in the tank (my first attempt ended up with rust in the bottom because there was still a little bit of water left, thats why I did 3 rinses with acetone).  Then, before the acetone even dried all the way I poured the marvels/gas mix in the tank (Only one quart) and sloshed that around.

[Dave-and-his-550]

Ya, after I rinsed the water out, I used the acetone but as I poured it in there, I noticed it started to get rusty RIGHT away. I was like wtf?! So, I used The Works again to fix it up, washed it out, but forgot to seal/coat it.

WHAT product am I suppose to buy that has Phosphoric Acid?? I can't just buy it pure, I called Lowes, Menards, Tractor Supply, they have no idea what I'm talking about when I ask for phosphoric acid.

I found THIS LIST of products that contain Phosphoric Acid:

http://hpd.nlm.nih.gov/cgi-bin/household/brands?tbl=chem&id=93

I don't know what specifically I'm suppose to get.

[Patrick]

Call the paint department at Lowes and tell them you are looking for Rust converter. It's green liquid. I've bought it at the local Lowes. It's near the naval jelly. If they tell you they don't know what you're talking about, ask to speak to someone who has ever painted steel.

Patrick

[Dave-and-his-550]

Ok I'm going to try this whole process over again tomorrow. So tell me if this is a proper order to do it in:

-Pour 'The Works' into tank and swish it around for 5 minutes. Pour it out and repeat. (This should be enough to get the rust off I think.)

-Mix powdered laundry detergent with warm water (Maybe a cup of detergent for each gallon of water?) And pour it in.

-Swish the water/detergent around for 5-10 minutes, dump it out and repeat.

-Remove as much water as possible, air dry it, and then pour in acetone (How much Acetone?)

-After I remove as much acetone as I can, should I let it air dry for awhile or pour in Marvels Mystery Oil and let that coat the whole inside? Should I let that sit in there for awhile? (If so, how long do you think it would help?)

-After I get out the oil, then do I have to fill it all the way with fuel to prevent it from flash rusting again? Or can it stay partially empty?

This will be my third attempt, and I haven't lost my patience yet.

[Patrick]

Swish the laundry detergent around, but also fill the tank and allow it to sit for a while. I usually let it go for at least 20-30 minutes, but an hour or so would be fine. You want all the acid neutralized and the inside of the tank clean. Swish again, empty and rinse with fresh water. Then dry with compressed air. I don't use acetone, so I can't advise you on that.

Patrick

[Dave-and-his-550]

I think the acetone is used to neutralize, or absorb the water thats left in the tank, I'm not exactly sure but hapsh mentioned it's helpful.

[hapsh]

Yes, the acetone absorbs the remaining water droplets and vapor that is still in the tank.  When you pour out the acetone it carries the water with it.  I found 2 applications of acetone worked well.  However, I did not wait until the acetone was completely dry in the tank to add the oil/gas mix.  If you leave the tank open with the oil coating the tank, the remaining acetone will evaporate fairly fast.  One thing to consider is your humidity level in your area.  I did my tank when it was totally clear outside and very low humidity.  If you live in a fairly humid environment it may be better to use the phosphoric acid method.

[Dave-and-his-550]

If you live in a fairly humid environment it may be better to use the phosphoric acid method.

Ya the ground is still wet here, and it has rained the last couple of days...The good news is, I have found the rust converter products that contain phosphoric acid, at Walmart and Orielly's Auto Parts. They are VERY small bottles though, and $4 a piece, I think I'd need like 4 or 5 of them to be able to coat the whole tank, and I've already spent $50 on materials 

I think I'd rather take my chances again with the $1.25 bottle of The Works.

[paulages]

a little 2 stroke oil in some fuel swished around inside will protect it as well.

[Cvillechopper]

Evaporust will get rid of the rust and leave a coating for several weeks that'll keep it from rusting until you're ready to coat.  Just rinse well, dry over night, and coat.  I had absolutely NO rust after the muratic acid bath, Evaporust over night, a week waiting, then rinsing the residual evaporust out, and drying over night.

It's not cheap but it works and you can use it over and over again. 

Good luck.

[Hope]

I am sorry to hear that you have 3 attempts and you're out $50.  You'd be done by now and you wouldn't have spent as much if you would have used POR15.

[dkruitz]

No need to let it fully air dry after rinsing with water, you want to use the acetone or alcohol to get the rest of the water out ASAP.  Letting it sit around to air dry will help cause flash rust.  Use 2-stroke oil, POR15, or fill it with gas to keep it from flashing.  Phosphoric acid from HD worked great on the suzukimatic I helped my brother-in-law with, and a 2nd coating per the instructions helps lay a carbon layer on the metal for protection - seemed to work on his.