Would you de-rust this tank? video scope

[Andrew Vanis]

Pic attached.

I wouldn't normally think I'd de-rust this tank. However I happened on the video scope on Clearance at Home depot (worth $75?) and I found significant BUBLING RUST in both backs of the tank. Much worse behind the petcock valve. Sorry no pics of the rust..using the scope is much more challenging that you'd think and taking pics of the screen didn't turn out well anyway.

Guess I'll have to become a electroalisys (sp?) expert.

Side queston, is POR15 still the choice or are there other options? and it is better to order it or is it usually avail locally (like NAPA)?

[Ghostgs1]

If it looks bad, then yes and maybe go ahead with the POR 15 when finished. I think you might want to try just using vinegar in the lower section if the rust is only very low in the tank, the center looks pretty good from what I can see. Ray

[Bookmon]

There are those who would say "Just put in some screws with some gas and shake it real hard".
I do agree with vinegar to neutralize.
I've yet to see any addative/coating get 100% approval.
I'd stick with ghost.

[BiPolarBear]

I've de-rusted many tanks by sealing the openings, except for the filler neck, and pouring in about two cups of muriatic acid, available from pool supply houses or big boxes, like Home Despot.

After you pour in the acid -- and wear gloves, it's vicious -- put the filler cap on, and shake the tank for a few seconds, and then move the tank around to keep the acid where the rust is heaviest. It doesn't take long, and you shouldn't keep the acid in the tank for longer than about a minute, anyway.

BE VERY CAREFUL opening the filler cap. The reaction produces toxic gas that is truly evil. Don't even bother pouring the acid out -- just shove a garden hose into the tank, back away, and turn the hose on full blast. It will flush the tank. Then you can remove whatever you used to seal the petcock and fuel sensor openings, and flush a bit more.

Them empty the tank as best you can. To prevent flash rust, I pour about a cup of WD40 into the tank (after resealing the petcock and fuel sensor openings, if you're not using the tank immediately) and swish it around to coat the interior.

I personally don't care for any of the tank coatings. If I store a tank empty, I coat the inside with WD40, and otherwise I keep them fully fueled.

[chuck hahn]

But what happens if your Muratic Acid opens up a pin hole that previously didn't leak? How do you feel about tank liners then?


A tank liner should go in if it has already rusted once ( least in my opinion ).


WD and gas aren't gonna stop it from rerusting in the long run....or from micro chips from flaking off and getting into the fuel system. The liners will permanently seal the tank from rerusting and also encapsulate anything the flush and fill has missed.

[BiPolarBear]

Respectfully, I must disagree.

First, if the acid opens up a pinhole, then the tank metal is too thin for me to trust a tank liner to contain the gas, especially in a collision.

Second, I just installed a tank that I de-rusted and WD40's in 2003, and it's as clean and shiny on the inside as the day it came from the factory. I sealed all the openings with duct tape before storage.

Third, again upon the structural integrity issue, after a tank is coated, it's impossible to inspect the inside of the take with fiber-optics for problems.

Forth, I've never heard of 'microchips flaking off', and have never had any experience with them.

Lastly, I am simply reporting what I've done in the past, and has worked for me with no problems -- ever.


BTW, if you go the "....put some screws and gas in it and shake" route, it's sometimes difficult to get ALL of the screws out. I have a friend that uses a dog chain collar -- much easier to remove.

[BassCliff]

Hi,

It's your call, of course, as to how bad the rust is. Mine looked worse than yours and my tank cleaned up nicely with Evapo-Rust. You'll find a couple of tank cleaning "how to" guides on my little website. Feel free to look through them when considering your course of action.

Tank Cleaning: with electrolysis

Tank Cleaning: with Evapo-Rust

Thank you for your indulgence,

BassCliff

[chuck hahn]

Muratic Acid seems a bit harsh...and depending on if someone wants to save the paint will dictate the best way to go about it.

[Andrew Vanis]

It's your call, of course, as to how bad the rust is.

I wish I could show you the rust in the corners - bubbling and flaky. Nothing like the filler neck, that was the surprise and the benefit of the video probe.

Those cleaning links are great. read them for fun even before I discover this issue. Like others have said, thanks for the great site.

So far I'm thinking manualy scrape the rust that I can. since most is behind petcock I can access through fuel level sending unit access hole. then thinking I'll fill with evaporust, now avail at my local home depot. I'm thinking a gallon with the tank held vertically (aft corners at the bottom) would submerge the most affected area. Then keep it full of gas. I figure this way I can still coat it in the future should the need develop (and this bike actually become roadworthy)

My scientific/geeky self really wants an excuse to use the electrolysis but its a whole lot more involved especially considering the current status of this rebuild.

Question on the evporust. Other than turning the metal black, any issue leaving it in the gas tank long term - like weeks?

[BiPolarBear]

Muratic Acid seems a bit harsh...and depending on if someone wants to save the paint will dictate the best way to go about it.
__________________

Yes, muriatic acid IS harsh -- and fast, and thorough. If you pay attention when you pour it in, there won't be any on the paint, but even if you do (as I have) spill a bit, just wipe it off, as you do when you spill brake fluid.

You may want to try it on a clapped-out tank, just for practice. You might be surprised by how easy and effective it is.

[chuck hahn]

I think I would dissolve a cup of baking soda in some water and dump it in to at least neutralize the acid before rinsing it out on the paint...or anything else!!!

[BassCliff]

Hi,

Question on the evporust. Other than turning the metal black, any issue leaving it in the gas tank long term - like weeks?

The Evapo-Rust did not turn any metal black in my case. But I didn't leave it in the tank for weeks. There's really no need to leave it that long. It should do its work in 24 hours. The liquid is environmentally friendly and will not damage paint, puppies, flowers, or anything else. It shouldn't hurt anything to leave it in your tank for a week or two.


Thank you for your indulgence,

BassCliff

[gsgeezer]

I was curious about Evapo-Rust, thanks for the info!

I don't cream them myself, I just take the old tanks to a local rad shop who blasts the inside and bakes on an epoxy coating. It is not expensive and I had bikes for years after doing this and never had a problem.
(The guy does this for antique cars and bikes.)

He even saves the original paint, if you want him too, by masking everything off.
(It costs a bit more to do that, so if I am going to repaint I don't bother with that step.)

[rustybronco]

As long as we're debating this subject, it might pay to use De-ionized water to rinse out the fuel tank instead of clorinated tap water.

http://thegsresources.com/_forum/showpost.php?p=1867721&postcount=1

[Andrew Vanis]

So I decided on the Evapo-Rust route. First I scraped a coat hanger around the corners and came up with this (as seen through the fuel gauge access hole)



Pretty big difference than the “clean looking” tank, huh?



Then poured in the Evapo-Rust and found this pinhole (stating a different post on welding)



The questions are –

1) considering that the rust is as bad as it was and that there is a pinhole, (once I fix the pin hole) should I continue the Evapo-Rust or should I go to eloctoalilsis
2) after welding, should I coat?
3) Is POR15 the recommended or should I include “Kreem” with my incoming Z1 Order?



Thanks,
Andrew