What's your favorite tank treatment?

[Guest]

I have a GS1100ESD tank that has been sitting with some old gas in it for maybe 15 years, and it is crusty inside, really crusty.

I've already started with my usual Berryman, CLR, Evaporust, juices to little avail. I'll likely progress to muriatic acid soon, but I thought I'd solicit ideas from your collective wisdom first.
I've now already screwed up the (formerly very pretty gloss black) paint, so I will now need a respray in any event, so any sort of nasty, caustic stuff is now fine with me.

I've heard good stuff about the 3 step treatment and sealer from Bill Hirsch, but I'm sure there must be home-brew remedies that work just fine and won't run $60.

Love to hear your own ideas.

Thanks,
Frank

[Nessism]

Varnish needs to be removed before you can derust and the chemicals are different between these two treatments. Berryman's should remove the varnish, but you need to allow enough time and keep the surface submerged before the sauce can do it's thing. After the varnish is out I prefer to use phosphoric acid to derust. It's the standard product for derusting in industry and works well. To derust a tank it takes about 24 hours or so, but that may have to be extended if the rust is extreme. Anyway, there are dozens of threads in the archive about this topic so I'll stop here and encourage you to search out more info.

[Rust_to_Redemption]

I assume you've already tried putting something small and metal (I like steel BBs) and shaking the bejesus out of it? After you get all the big flakes off with that, you can clean up the surface with a 1:1 mixture of fine sand and distilled water (usually used half a gallon each) and more shaking. Does a really good job to prep the surface for sealing.

[fastfrank]

I assume you've already tried putting something small and metal (I like steel BBs) and shaking the bejesus out of it? After you get all the big flakes off with that, you can clean up the surface with a 1:1 mixture of fine sand and distilled water (usually used half a gallon each) and more shaking. Does a really good job to prep the surface for sealing.

Yeah, I use a chain inside instead of dealing with lots of nuts & bolts or whatever - I like that I can grab one part and get it all out, and it's done a great job for me in the past. I eventually get my 20-yr old twin boys to do the shaking.

[fastfrank]

Varnish needs to be removed before you can derust and the chemicals are different between these two treatments. Berryman's should remove the varnish, but you need to allow enough time and keep the surface submerged before the sauce can do it's thing. After the varnish is out I prefer to use phosphoric acid to derust. It's the standard product for derusting in industry and works well. To derust a tank it takes about 24 hours or so, but that may have to be extended if the rust is extreme. Anyway, there are dozens of threads in the archive about this topic so I'll stop here and encourage you to search out more info.

I'll peruse the other threads, thanks. I had the Berryman's in there for two days, I think, but it does look like it isn't de-varnished yet. I'll just have to give this one some more time.

[Nessism]

Something small with sharp edges works best to reach all the nooks and cranes and scrub the metal. This won't derust the tank though, for that you need chemical assistance.

[HiSPL]

Has anyone gotten a radiator shop to dip the whole tank in their acid bath? I have an old tank that I might try that on. I was gonna repaint it anyway.....

[trevor]

I used metal rescue on my cooley tank after using cider and small bolts, washers and nuts to shake the rust off....

Metal rescue filled to the top sit for 48 hrs then sealed the filler hole with a lacrosse ball and tipped it upside down for another 48hrs....rinsed out with Methyl Hydrate a few times....no rust again....best part is Metal Rescue will not harm your paint and can be used over again.

[alke46]

Has anyone gotten a radiator shop to dip the whole tank in their acid bath? I have an old tank that I might try that on. I was gonna repaint it anyway.....

This is the route I took with mine. As hard as I tried, I could not get all the old liner out, especially the hump in the center of the tank. My radiator guy sent the tank out to someone who then burned all the old liner out. After that was done, he dipped it in acid and put in a new liner.
FWIW, this radiator guy is the son of a guy I have known for years. He does restorations on old items such as cars, trucks, and tractors. He is a perfectionist so I have complete confidence his work was done right and I will never have to worry about my tank again.

[fastfrank]

Yeah, the TIQ (Tank in Question) is from my 83 GS, and it was never lined, but I do have another one, on my KZ750 twin, that has an old Kreem job from the previous owner, and the liner is peeling and generally self-destructing. Likely due to ethanol and occasional fuel treatments, and maybe just a bad choice in tank liner to start with. I have a hard time keeping the pilots clean and usually have to partially choke it to get a higher idle. Since it is a running bike I can ride right now, and I can deal with the high idle, I'll rework that tank after I finish getting my GS and ZRX fully road-worthy :-) I want a clean tank for the twin, since I'm going to install VM34 carbs, and I don't need to gunk those up, too.

[fastfrank]

BTW, the chain I use to treat tanks inside is well known on the ZRXOA forums... from Lowes, it is a #200 twist chain, Blue Hawk brand. They have twisty flats on the them and dig in pretty well. Easy to remove at the end of the process, and reusable.

[fastfrank]

I appreciate all the ideas. I might just consider a radiator shop; sounds like a good idea.

[Steve]

I know it won't help you much, but you asked about "favorite treatments".

MY favorite treatment is fresh gas every once in a while, which I insist on burning off, several miles at a time.

.

[fastfrank]

I know it won't help you much, but you asked about "favorite treatments".

MY favorite treatment is fresh gas every once in a while, which I insist on burning off, several miles at a time.

.

Amen, brother

[Greg B]

Good radiator shop. Look for one that is known for doing tank restoration. My XLCR tank took nearly a month to clean the 40 years of crud out of it. But, no acids, and the actual holes that were poorly repaired with fiberglass were properly patched by brazing.
Wasn't cheap, but with an original tank, it's with the money.