Topic: Whats a good way to remove flash rust after treating my tank w/ vinegar ?

[grcamna2]

Just did the 12 hr. straight vinegar in my tank and it flash rusted before I could dry it;it'd be nice if I could just flush all that flash rust right out'a there. Any ideas ??
A way to protect it from flashing again ?

[seanbarney41]

more vinegar will quickly remove the flash rust.  This time you gotta have all your ducks in a row and work FAST.  Be sure the tank is filled to the tip top with vinegar.  Have a five gallon bucket of hot tap water mixed with baking soda ready BEFORE you dump out the vinegar.  Also have a jug of acetone ready to go.  As soon as the vinegar is out, dump the baking soda water in.  Then immediately dump that out too.  Flush the tank out with a hose really good then get as much water outta there as you can, FAST.  Gotta be a little careful with the acetone as it can damage certain paints if in contact for too long.  Pour in as much acetone as you can afford and swish it around to absorb as much water as possible.  Dump the acetone.  Blow dry the tank with compressed air, or a hairdryer.  Coat the inside of the tank with wd40, or any other light, sprayable oil.  If the tank is not going into immediate service, coat the inside with a heavier oil such as two stroke or mmm.  You gotta have all this stuff prepared and ready to go and work FAST!  Last time I did this I was quite winded by the end of the process.  I have seen some tanks end up with a rust colored tinge inside after all of this, but there should be no flakes, pits, or powdery rust, and the tinge will not get any worse.  Good luck.

[ekpent]

I have a shop vac that is also a reversible 165 mph blower. When I stick the end of the hose in the tank and the petcock holes open that baby dries out very fast and cheap and then get gas back in it right away. Little dash of 2 stroke oil won't hurt anything if it going to be sitting for awhile, give it a swish every so often.

[goldarrow]

Or you can go with high end commercial products cost about $25/gal and take your time and not worry about flash rust

[grcamna2]

more vinegar will quickly remove the flash rust.  This time you gotta have all your ducks in a row and work FAST.  Be sure the tank is filled to the tip top with vinegar.  Have a five gallon bucket of hot tap water mixed with baking soda ready BEFORE you dump out the vinegar.  Also have a jug of acetone ready to go.  As soon as the vinegar is out, dump the baking soda water in.  Then immediately dump that out too.  Flush the tank out with a hose really good then get as much water outta there as you can, FAST.  Gotta be a little careful with the acetone as it can damage certain paints if in contact for too long.  Pour in as much acetone as you can afford and swish it around to absorb as much water as possible.  Dump the acetone.  Blow dry the tank with compressed air, or a hairdryer.  Coat the inside of the tank with wd40, or any other light, sprayable oil.  If the tank is not going into immediate service, coat the inside with a heavier oil such as two stroke or mmm.  You gotta have all this stuff prepared and ready to go and work FAST!  Last time I did this I was quite winded by the end of the process.  I have seen some tanks end up with a rust colored tinge inside after all of this, but there should be no flakes, pits, or powdery rust, and the tinge will not get any worse.  Good luck.

Gotcha Sean   
MAN Alive,that's a marathon event to get it right !  Have you ever used another product to finish it off instead of this whole production such as a 1 gal. bottle of Evaporust swished around a good bit inside my little 2.5 gal. tank ? Would I still need to completely dry it after rinsing it out w/ that stuff ? or anything else?
I've got this procedure here written down now so I can refer back to this post(thanks Sean) later on.Does it matter whether it's warm or cold outside ? I did the vinegar treatment in my little Apartments bathtub over the course of 24 hrs.I finsished by putting my PC'd tank in the oven at 240 degrees for an hr. w/ just a little water left inside of it hoping the heat of the oven would dry it up...,now I suppose(after reading your post)that I must have created a type of 'steam bath' inside that tank and made it worse.I guess I'm just going to need to find a high volume/low pressure air pump to get it done quick similar to what Eric mentioned in his post. I don't have access to a shop w/ water hose outside that'll let me make use of the area for a while so I imagine I'll have to use my Apt. again to repeat.
                Thanks

[seanbarney41]

I seem to be the only one to use Evaporust that found it to be nearly useless.  De-rusting gas tanks in an apartment is gonna be a big challenge.  I do it outdoors during tolerable weather.

[grcamna2]

Sean,I can use the 3 empty vinegar gallon jugs for baking soda rinse;I'll need to work out how to dump the acetone(a sealable container)and then the high volume/low pressure blower machine.I'm going to get every last bit of flash rust out of that tank(it's sitting w/ some oil for now sealed up)because I hate cleaning carbs.

[grcamna2]

Cal,Denatured alcohol will dry that water up? That doesn't smell as bad as diesel.

While you're avail.,can you tell me what's a good process for 'clearing in' a pr. of decals onto my PC'd tank ? I have a plan..,but first I'll describe the tank/bike
 The whole bike has been PC'd black(it was black from the factory)and the tank isn't meant to be 'show quality'  but it is protected and uniform w/ a few little defects/dents under the coating.. just to let you know of the outside cond. of it. I'll be using the bike as a 'beat it & drive it all over in all kinds of weather' Basic Transportation machine and carrying stuff on top of the tank,etc.
  I want to mask off a section of a little less than 5" round,and then sand down the black PC inside that round area w/ a fine grit(1000 ?)paper and then apply my 2) Honda wings L.&R. inside those 2 masked off circles & possibly lightly scuff the face of the oem Honda decals just a hair and then spray some clear lacquer over that round masked off area,let it dry and remove the masking and have 2 shiny 5" round decal 'circles' w/ a Honda Wing underneath the clear on either side over the standard PC gloss(which isn't too glossy)and hope that fuel will not wash'em off.
Do you think it'll work as a plan ? I'll wait until I finish removing the flash rust first.
Thanks for your feedback 

[grcamna2]

Yep DA will dehydrate all the moisture. In fact, if you leave the container open overnight, you'll come out to find an empty can in the AM. It's the single most used chem in my shop, even more than WD, PB, and Acetone.

Regarding the clear over PC, know way to say. Depends entirely upon how tight the PC is whether the clear will bond to it where you didn't sand it. If it were me, I'd scuff the whole surface with 600, lay a single cost of black, decals, then clear. With a PC base, a single shot (or 2) of black will be easy and inexpensive, thus allowing proper adhesion for the clear since you'll have flash time available. And if your black isn't full coverage, the undercoat will fill in the flaws.

An idea anyway....

Cal, I plan on completely sanding the entire surface of the masked 5" round circle w/1000? before I apply the clear over the decal,I want to prep/sand all that area and a little on the decal.How have your results been w/ applying lacquer over sanded PC ?

[grcamna2]

Never have done it that way. Sorry. If I PC, it's the final finish, or, I use as a corrosion prevention base then Bondo, epoxy primer, and PPG the final coats. That's why I suggested sanding the whole thing enough for adhesion of a quick flash coat of black again and proceed from there.

ok,thanks

[grcamna2]

I'd offer different advice than Sean. Don't use Acetone unless you're not concerned about potential paint damage. Instead, after the neutralizing bath, use Dentaured Alcohol. It will wholly evaporate the moisture in the tank and is completely paint safe.

Another option, is to use 1 gallon of Diesel, drain vinegar, quick flush, then Diesel. Generously tumble the diesel about, drain. It will coat and protect the metal from flashing, and upon installation, it will dilute very quickly in the gas. Downside, if you're in an apartment, the odor will drive you OUT! Proceed at your own peril with this method-

Cal,I purchased the Denatured Alcohol and tested a bit w/ it by pouring some out onto a surface,it does take it a while to evaporate... My question is when I finally do my last flush and then throw the Denatured Alcohol into the tank and swish it around,it may still take it a while to evaporate...;during the  time it takes the 85% denatured alcohol/15% water mix(the reason I say 85%/15% alc./water mix is because there will be a little water in the tank I won't be able to drain from that single small lower petcock opening quickly enough...,my tank takes a little while to drain...)to  evaporate....my question is,during the time it takes the denatured alc. to evaporate won't it still flash rust while it's trying to dry ? That denatured alcohol doesn't dry up REAL fast & I was concerned it would still cause me a problem w/ 'flashing' 
I want to hear your thoughts on this because I have the tank full of vinegar now and want to go to the next step   
   I sure don't like the smell of diesel in my apt. but just want to make that d*mn flash rust 'go away'    or will I need to buy another product to get rid of the flash rust in a different way ??

[grcamna2]

If you've flushed and rinsed with DA, then whatever remains in liquid form will prevent flash rusting whie it evaporates.

If you want, you could use Prep and Etch or other treatment, but they also encourage promptly filling with fuel. You could rinse the vinegar and fog the tank with WD or pout a 2-cycle oil through if you're not going to fill with fuel promptly. About anything that either dehydrates fully or coats the metal with protective petroleum film with be more than suitable. Storing the tank indoors? Should also regard rusting.

That's a relief ! to hear that the denatured alcohol won't 'flash up' like the water,I'll get it in there as fast as I can then.
I also will be putting around a 1/2 pint of  2 stroke oil swished around inside it once all the denatured alcohol is dried up.. & I'll leave it in there until Spring when I'll fill it w/ fuel again.

[goldarrow]

From what I read so far, your challenges are limited working space and time to work in between the process. 

I'll post my 3 cents opinion.....

More to come...

[goldarrow]

so...given your scenario.  here's what i would do.

since you're in apartment and apartment normally comes with bath tub.  so i would get a shower hose something like this http://www.homedepot.com/p/RINSE-ACE-Assisted-Bather-with-8-ft-Extra-Long-Quick-Connect-Detachable-Hose-and-3-Setting-Sprayer-Pause-Mode-3520/202340030   long one, used one from garage sale for a buck may be?  remove the handle. 

get a children's plastic play chair so you can sit comfortably in the bath tub while working?  http://www.ikea.com/us/en/catalog/products/30267559/  may be a buck at garage sale again???

take your tank with you into shower tub, pretending you're taking shower with your tank just kidding  flip the tank upside down, then hose the !@$!@$!#$ out of the tank from the petcock hole so it drains down through the filler hole.  or i think it's better to stick the hose into filler hole, then flip tank upside down, then blast inside the tank.  good thing about being in apartment is that water is already prepaid in the rent, so no worry on water bills, but still do try to conserve water though   we're going through drought here in CA lol

once done with water flush, then use your chemical of choice, i had only used evaporust and CLR, and non others (can't seem to find them at garage sale???) so i can't comment on other products.  fill the tank with chemical, along with some rusty nuts and bolts from the bike, shake it around, let it sit, shake it around, let it sit, repeat the process.  evaporust is slow process, CLR is much quicker and you see result in like an hour or so.....

by this time, you can flush again with water, but i don't, pour in some small amount of denatured alcohol like calj said, and do this couple of times. 

then follow by wd40

then follow by atf, mmo, 2 stroke oil, or other light weight oil

i know this is long write up, but when actually doing it, time goes by fairly quick, especially if you have everything you need right next to you by your bath tub

if this works out for you, please be kind to send 3 cents my way  

[flybox1]

KISS! 
empty the vinegar
pour in 1 pint fresh gas, shake, drain, pour in 1 pint fresh gas, shake, drain....
fill tank with fresh gas.
ride.

[goldarrow]

KISS! 
empty the vinegar
pour in 1 pint fresh gas, shake, drain, pour in 1 pint fresh gas, shake, drain....
fill tank with fresh gas.
ride.

I know right

[flybox1]

KISS! 
empty the vinegar
pour in 1 pint fresh gas, shake, drain, pour in 1 pint fresh gas, shake, drain....
fill tank with fresh gas.
ride.
pour in one pint of MMO, shaken, not stirred

There 

The old gas can be disposed of many ways.  Many of the auto parts stores where he'll have to buy his cleaning supplies will take old fluids.  If not, most dumps have a collection area for it.  The one near me doesn't even charge for it.

[eastyork1977]

If you're in an apartment chems are not an option, you gotta be efficient.

Baking soda method works but you do have to follow it up with something as well.

I use another natural etcher that is easily neutralized by water. Right after its all neutralized and dry inside, (I use a hair dryer, toilet sponge and shop towels on a bent rod), you can coat it with WD-40 or two stroke oil as mentioned.

Or just fill it right up with gas and ride if you can after all the chems and water are out.

Don't over think it though, just be prepared before hand.

[goldarrow]

Evaporust is environmentally safe, CLR use for cleaning kitchen and bathroom, so both are fairly safe.  They don't stink much either. 

Again, take my words with a grain of rice or salt...

[grcamna2]

KISS! 
empty the vinegar
pour in 1 pint fresh gas, shake, drain, pour in 1 pint fresh gas, shake, drain....
fill tank with fresh gas.
ride.
pour in one pint of MMO, shaken, not stirred

There 

The old gas can be disposed of many ways.  Many of the auto parts stores where he'll have to buy his cleaning supplies will take old fluids.  If not, most dumps have a collection area for it.  The one near me doesn't even charge for it.

I'm set-up w/ 3 gallon jugs of low strength baking soda waiting for when I empty the vinegar out of the tank through the single petcock hole on the left,I'd like to then(I'll do it this evening so thanks for these tips sohc4 members  )fill the tank w/ baking soda mix to the brim and then drain it right out again?(how am I doing so,far ?)and at that point... 'I have options,correct ?    Well,I was then going to fill the tank w/ plain water w/ the funnel and the 3 gal. jugs(is that too slow & will it allow more flash rust going that slow? I can see why goldarrow said "get a hose to fill the %*#@ out of it" I guess that means FAST,right ?)up to the top & then empty it again and at that point I was planning on emptying out as much water as I can just by allowing it to drain(I think at that point I must be going too slow,right?)and then the next step I was going to do was throw in 1+qts. of the Denatured Alcohol and shake it up real good and then drain out as much as fast as I can and then take my old Electrolux vacuum and attatch the hose to the blower side and blow it as dry as I can as quick as I can.
I'm entirely open to suggestions from you members because I'll probably be doing all this at 8-9 PM tonight(very quietly because of my downstairs neighbor  ) and kneeling/leaning over the side of my bathtub.I'm going to have 6 gal. jugs of water & baking soda mix;should I definitely use a hose or something to fill it w/ fluids quicker? is speed a good idea to keep air away from the freshly etched steel inside the tank ? I've been going about it slowly the last time.

Hey thanks for all your feedback because it's helping me refine my process;I only want to do this one last time and then coat it w/ oil and put the tank out in storage.I guess I could do just what Flybox said and use gasoline..but the denatured Alcohol should be about the same,right ?
I know,I know "don't over think this" but I want to make sure to get it right this time 

[grcamna2]

Settle down, you're inside and the flash rust shouldn't appear within seconds. If you're that bloody worried about it, after rinsing with baking soda, use Prep and Etch. Then fog or line the thing.

A bit OCD over this...

yeah, i'm glad I have some good guidance  .There's nothing like pure clear fuel into the carbs. to keep it running optimum & I want to have this steel fresh after all of this.I'd much rather not line this tank, but use it for years w/o rust,I plan to always keep'er full when outside too.

  I must admit I've gotten spoiled/lazy;for years I had Al over at Tirrell Radiator line all my customers tanks for me. I guess I must have overloaded him w/ tanks,me and the Harley shop where I used to live(once I told him about Tirrell)because I called one day for him to p-up a tank at the Hyannis Airport from me on the island and his boss told me "we won't be doing Any more tanks".
 I think it was the MEK that he was using to thin out the Redkote,that stuff is Not good for the brain cells...  or our health & I think that AL was getting sick.

[budman]

There's a product called Holdtight 102. It's a rust inhibitor that you put in water to keep steel from flash rusting.  It removes the chlorides and salts from the water. You've got about 48-72 hours before the bare steel starts to rust.  There are similar rust inhibitor products.

[grcamna2]

KISS! 
empty the vinegar
pour in 1 pint fresh gas, shake, drain, pour in 1 pint fresh gas, shake, drain....
fill tank with fresh gas.
ride.
pour in one pint of MMO, shaken, not stirred

There 

The old gas can be disposed of many ways.  Many of the auto parts stores where he'll have to buy his cleaning supplies will take old fluids.  If not, most dumps have a collection area for it.  The one near me doesn't even charge for it.

I'm set-up w/ 3 gallon jugs of low strength baking soda waiting for when I empty the vinegar out of the tank through the single petcock hole on the left,I'd like to then(I'll do it this evening so thanks for these tips sohc4 members  )fill the tank w/ baking soda mix to the brim and then drain it right out again?(how am I doing so,far ?)and at that point... 'I have options,correct ?    Well,I was then going to fill the tank w/ plain water w/ the funnel and the 3 gal. jugs(is that too slow & will it allow more flash rust going that slow? I can see why goldarrow said "get a hose to fill the %*#@ out of it" I guess that means FAST,right ?)up to the top & then empty it again and at that point I was planning on emptying out as much water as I can just by allowing it to drain(I think at that point I must be going too slow,right?)and then the next step I was going to do was throw in 1+qts. of the Denatured Alcohol and shake it up real good and then drain out as much as fast as I can and then take my old Electrolux vacuum and attatch the hose to the blower side and blow it as dry as I can as quick as I can.
I'm entirely open to suggestions from you members because I'll probably be doing all this at 8-9 PM tonight(very quietly because of my downstairs neighbor  ) and kneeling/leaning over the side of my bathtub.I'm going to have 6 gal. jugs of water & baking soda mix;should I definitely use a hose or something to fill it w/ fluids quicker? is speed a good idea to keep air away from the freshly etched steel inside the tank ? I've been going about it slowly the last time.

Hey thanks for all your feedback because it's helping me refine my process;I only want to do this one last time and then coat it w/ oil and put the tank out in storage.I guess I could do just what Flybox said and use gasoline..but the denatured Alcohol should be about the same,right ?
I know,I know "don't over think this" but I want to make sure to get it right this time 

Success ! 'the bathtub flush' worked and kept me moving at speed too  I finished it off w/ the Denatured Alcohol: 'shaken,not stirred'  and then blew that sucker out w/ my old Electrolux which got it warmer also as a bonus.I had no heavy flash rust like last time,just a little orange dust that i could wipe off w/ my finger ! I just would rather use the stock steel tank w/o a liner as long as I can & then down the road in a few years maybe I'll have to line it.This little tank has a lot of baffles where the filler neck just about touches the center tunnel so it's a challenge to be able to tell if I got as much rust out as I should have.The good news is that every time(3) I filled it w/ vinegar and left it sit and drained it more rust came out.My carbs. are going to be smiling this Spring  I coated it w/ a product called Ampco which is an old fashioned 'top end firing zone lube' similar to 'Firezone oil' which was a competitor years ago. People used to add it to there fuel tank to help the rings/valves make a better seal and it would also help to loosen up carboned rings,etc.,it's just like MMO in it's function.I'm confident she's done now,so On to the next tasks.
                              Thank You sohc4 members 

[grcamna2]

There's a product called Holdtight 102. It's a rust inhibitor that you put in water to keep steel from flash rusting.  It removes the chlorides and salts from the water. You've got about 48-72 hours before the bare steel starts to rust.  There are similar rust inhibitor products.

Hey thanks budman,I appreciate that.