Topic: Cleaning out the gas tank question

[Guns_Up]

Hello everybody,

     My tank has the smell of old and sour gas, I am looking to clean it out and reseal it the best way possible. I have searched and searched (using the search button) and have come up with little to no help. The Evapo-rust post I have found said "works great on tools with a shot of wd-40 afterwards" but that really doesn't help out with the gas tank, I have seen the the post about cleaning it electronically will the re-bar and the solution, but in that thread guys were saying there were better ways to do it, but never elaborated much past that.

     What I am looking for is - what have you used that has worked and what the process was you used to get your results.

Thanks guys,
Tony

[Teatimetim]

I used reverse electrolysis http://www.instructables.com/id/Electrolytic-Rust-Removal-From-A-Motorcycle-Gas-Ta/

It worked well but  you need a little paitence.   I then sealed the tank with POR-15 starter kit.

You need a week, a battery charger, and some Baking Soda or I used Oxy clean

Not the fasted way, but the rust was gone.

[Teatimetim]

And before I forget, I covered the petcock studs and tube wholes with waded up telflon tap, and then used duct tape to hold them in, with no leaks.

[killersoundz]

Rusty Gas Tank Cheap Fix


try this

[vistirus]

How bad is your tank?  How old is it?  Is it close to being rusted through? My tank is a '78 and not too bad.  I took out the petcock and plugged the hole with a rubber stopper. Dumped 2 bottles of Pine Sol in, filled with water (5 gallon tank). Soaked for 24 hours. I was amazed at how it cleaned out the grunge that was in there. Washed it out with a garden hose and then filled with 5 gallons of white vinegar (total cost $5). I let this sit for a week. It will eat through the rust on the inside, but it also attacks metal, so you need to watch  it if your tank is thin (maybe try something else). Dump this and again, clean with fairly high pressure water and air. Be sure to get all the rust out. You should see clean metal inside. Now fill the tank with clean water and dump in a box of baking soda. It is a base and will neutralize the acid.  Clean this out, flush out with water, spray air around inside then dump in a pint of 2 cycle oil and swirl it around to coat the inside and prevent flash rusting. Then fill it with fresh fuel right away. Sounds like a lot to do, but it just takes some time. This worked for me. The pro shops generally use the electrolysis method, and it may work the best. But I just didn't have the equipment needed to try that.

[Randy]

i took out the petcock and used o rings and bolts to plug the holes and a fuel hose and a bolt to plug the main hole.. the I poured one gal of Smart and final toilet bowl cleaner and the rest with hot water.. i let it set overnight.. dump some out and find a dollar store duster the is long enough to reach over the hump.. Adjatate and dump and clean with water.. then get some fuel in it as soon a possible

[Accolay]

How bad is your tank?

+1

Here is a fairly comprehensive overview of methods: http://www.mopedarmy.com/wiki/Removing_rust_from_a_gas_tank

I personally used toilet bowl cleaner "The Works" brand I think. I had some good flash rust and no flakes. Don't forget to remove the fuel strainer! I believe people have coated with ATF afterwards. I used a small rubber stopper I found at Ace Hardware to plug the petcock hole.

[BeSeeingYou]

You may have a gas varnish build up that has to be removed first.  You need some type of heavy duty de-greaser.  I used Industrial Purple, some use Simple green, I am sure there are others.  Acids or electrolysis will not take the varnish out.  Once that is done you can see if there is a corrosion problem.  If you have light surface corrosion maybe an acid wash would be the way to go.  I would tend to use Prep and Etch, a phosphoric acid that is not too aggressive and leaves a phosphate coating that protects against flash rust.  This is one acid where you do not use the baking soda to neutralize.  If you have deeper flaking corrosion maybe the electrolysis method would be best as it will not remove any good metal.  An acid would have to sit to long in the tank for this deeper corrosion. If the tank is solid and not compromised just get it clean, no need for a liner.  Weakened by corrosion, maybe with pinhole leaks go for the liner but follow the application directions 100% with no "improvements" or shortcuts on your part.  And like others have said "don't do any of this with the petcock mounted on the tank".

[750K]

If its rusty I second the vinegar soak, heres a link to a thread.

http://forums.sohc4.net/index.php?topic=64952.msg1169072#msg1169072

Half way down page 2 are pics of my now rust free kz1000 tank. If its just crud and varnish I'd go with simple green or carb clean as a soak cleaner.

[grcamna2]

I've got some heavy flash rust on an otherwise nice tank that I don't want to coat...the flash rust is from a guy I contracted who used something in there and just never properly rinsed the tank..or Dried it & just left it to sit and hope it would air dry 
and to think I paid him to do it ! the tank was very nice at first but had been sitting & had just a little sediment in the bottom which I hoped he could just flush out quick.
What type of treatment do any of you recommend for it to keep that flash rust from getting worse ? Will an acid wash phosphate like srust58 recommended be all I need ?

[BeSeeingYou]

I've got some heavy flash rust on an otherwise nice tank that I don't want to coat...the flash rust is from a guy I contracted who used something in there and just nbever properly rinsed the tank..or Dried it & just left it to sit and hope it would air dry 
and to think I paid him to do it ! the tank was very nice at first but had been sitting & had just a little sediment in the bottom which I hoped he could just flush out quick.
What type of treatment do any of you recommend for it to keep that flash rust from getting worse ? Will an acid wash phosphate like srust58 recommended be all I need ?

The Prep and Etch is similar to Evapo Rust that some have also recommended on other threads.  On that light brown flash rust it will work fairly fast, maybe in a matter of minutes.  Follow the directions on the jug.  The vinegar works too but is much slower and you still have the problem of rinsing and drying before it flashes again.  Probably easier on the paint (and your hands)  if you spill though I had no problems.  The Prep and Etch is left to dry in the tank and it leaves the coating but I think you still need to get the left over tablespoon or two out that seems to always stay in the tank.  I tipped my tank up and used an old rag wrapped around a coathanger to soak it up.

[Guns_Up]

How bad is your tank?

+1

Here is a fairly comprehensive overview of methods: http://www.mopedarmy.com/wiki/Removing_rust_from_a_gas_tank

This link should definitely be stickied some where, unless it is and I couldn't find it

The tank itself is a '75 and in great shape, the paint is very nice on it, so not harming the paint to take into consideration. The gas that was in it had been in it for roughly a yr or so. I can not see a large amount of rust when I open the tank on the hump. But that doesn't mean that there isn't any in there and if I am going to to it I might was well do it all out. I think that the POR-15 kit would be the best route to take for my tank b/c it is not incredibly rusty it just needs to be cleaned really well.

Has anyone used the POR-15 kit and if so any words of advice. Thanks for the help and info guys.
Tony

[grcamna2]

When using the different methods for cleaning out the rust in my tank as described so far..,can I use some heavy plastic underneath my flip top O.E. gascap? to keep it from getting in to the inside of the cap and also seal it enough to turn the tank upside down so I can de-rust(or Evaporust )the top of the tank? Any one ever do it that way ??
I ask because I'd like to be careful w/ my paint job and keep it sealed.

[Accolay]

So many decision....There are many ways to remove rust. You just have to find the solution that works for you and is within your budget. Just do a search on google or YouTube. There are videos on people using everything from phosphoric acid, to electrolysis, apple cider, citric acid, vinegar and even molasses.

[grcamna2]

When using the different methods for cleaning out the rust in my tank as described so far..,can I use some heavy plastic underneath my flip top O.E. gascap? to keep it from getting in to the inside of the cap and also seal it enough to turn the tank upside down so I can de-rust(or Evaporust )the top of the tank? Any one ever do it that way ??
I ask because I'd like to be careful w/ my paint job and keep it sealed.

Anybody ?

[Teatimetim]

When using the different methods for cleaning out the rust in my tank as described so far..,can I use some heavy plastic underneath my flip top O.E. gascap? to keep it from getting in to the inside of the cap and also seal it enough to turn the tank upside down so I can de-rust(or Evaporust )the top of the tank? Any one ever do it that way ??
I ask because I'd like to be careful w/ my paint job and keep it sealed.

Anybody ?

I made a telflon tape roll, long like a duby and then fit it around the tank opening then used duct tap to secure it.  I have an older style tank though 76 cb550k though, I'm not sure what I would do with the newer style.

[Accolay]

When using the different methods for cleaning out the rust in my tank as described so far..,can I use some heavy plastic underneath my flip top O.E. gascap? to keep it from getting in to the inside of the cap and also seal it enough to turn the tank upside down so I can de-rust(or Evaporust )the top of the tank? Any one ever do it that way ??
I ask because I'd like to be careful w/ my paint job and keep it sealed.

Anybody ?

Maybe just stick something in the gas cap vent hole?

[BeSeeingYou]

When using the different methods for cleaning out the rust in my tank as described so far..,can I use some heavy plastic underneath my flip top O.E. gascap? to keep it from getting in to the inside of the cap and also seal it enough to turn the tank upside down so I can de-rust(or Evaporust )the top of the tank? Any one ever do it that way ??
I ask because I'd like to be careful w/ my paint job and keep it sealed.

If you are going with the Prep and Etch (or other acid) keep in mind that you don't need that much in the tank to remove the surface or light corrosion.  Just a cup or so and slosh it around.  My tank had  a collar on the inside of the fill hole so I could slowly rotate the tank and it not come pouring out the fill hole.  Of course you still want to find some way of sealing the hole.  I did this on a tank that was going to be repainted so I just wrapped a tight rubber band around some plastic wrap over the fill hole lip.  Gloves and eye protection in case of a splash.

[grcamna2]

Okay..I can block the vent hole..., but what will the cleaning agents/solvent or Evaporust do to my rubber gascap seal? it may leak out onto my paint if not sealed well.I just want to be able to get as much of that stuff up on the top of the inside of the tank also..where I can't see;anywhere rust will hide to do a Complete job.
What other type of Seals are any of you recommending to completely seal off the gas cap ?

[shade]

I am brand new to this and was able to do the electrolysis method without a problem.  Just make sure you use Washing Soda, not Baking Soda.
There are plenty of videos on youtube and here is a good site:

http://www.mopedarmy.com/wiki/Removing_rust_from_a_gas_tank

I would go with electrolysis, it is amazing how effective and simple it is.  Just takes time.

[BeSeeingYou]

While I don't recommend getting acid on the paint I have been using Prep& Etch to clean some parts of corrosion and it seems to take a while to affect any paint on the parts.  Just be ready to wipe off any that finds it's way onto the tank.  Had no noticeable effect on some rubber on the parts I was cleaning.

[grcamna2]

Thanks for that Information ! 

[lone*X]

I've cleaned a few over the years and have used several different methods.  From shaking sheet rock screws till my arms almost fell off, to vinegar, and phosphoric acid.  Vinegar is the cheapest at about a buck fifty a gallon but is acidic and you need to flush and treat the tank well afterwards.  Phosphoric acid is good and leaves a protected surface.   Recently saw a new WD-40 product advertised and was wondering if anyone had any experience with it.  A little pricy at $25 a gallon but if it does the job and is more friendly than the acids it might be worthwhile.  Flyer says it does not hurt paint which would be a plus if you have a good paint job you don't want to mess up.

http://www.wd40specialist.com/products/rust-remover/?utm_source=google&utm_medium=cpc&utm_term=soak_rust_remover&utm_campaign=rust_remover_broad

[grcamna2]

Don,
  I wonder if this WD-40 product has the same active ingredient as Evaporust ?

[Guns_Up]

I've looked more into the WD-40 "rust removal soak contain and this is what their website says

"What does WD-40 contain?"

"While the ingredients in WD-40 are secret, we can tell you what WD-40 does NOT contain. WD-40 does not contain silicone, kerosene, water, wax, graphite, chlorofluorocarbons (CFCs), or any known cancer-causing agents."

As for the Evapo-Rust I couldn't find anything on the active ingredients other then what it says on the actual bottle.

As far as the POR-15, I found this video on youtube, its 10 min long, with two British guys sealing an old car fuel tank, they go step by step and explain the details of the process in great detail.

Petrol tank repair with the POR15 kit

this is what I found, but are there any more words to the wise on making sure its sealed tight other then a "teflon tape duby"  to prevent the chemicals from leaking on to the paint?
 
Tony