Rusty Tank - What to seal/coat with?

[DMB]

So I have a very very very rusty tank. See Photos below.



I am going to do electrolysis on it starting tomorrow. After it is done (if it works) should I seal/coat the tank with anything so it doesn't rust again. I really don't want to put a thick sealer in the tank if I don't have to.

-The options that sound good from previous post are Caswell PHENOL NOVOLAC EPOXY GAS TANK SEALER, POR-15, Hirsch MOTOR CYCLE TANK REPAIR KIT, and Sudco Rustol. The Sudco Rustol sounds pretty cool to me. Spendy, but concentrated.

-Or do I just spray it with fogging oil and then go and fill it up with gas right away and try to keep it filled up all the time.

More pics:







So what should I do?

[dardoonk]

That might be the worst looking tank innards I've ever seen.
How 'bout another tank??

[TheCafeKid]

Personally, i would look for another tank. But having done the electrolosis, it actually works suprisingly well. I am not entirely sure that its gonna get all of THAT, but it should do a decent job. Im not a fan of tank liners. I have read too many horror stories both on here and some of the other forums i belong to, to try one. So i would suggest, if another tank isnt an option, electrolosis, fogging oil, keep it full, and run and inline filter.

[tkent02]

Electrolysis should work well, won't hurt the paint if you only fill the tank and not dunk the whole thing. I just did one almost that bad, no worries, the rust is gone.

We definitely will be needing before and after pics of this one.

[psyguy]

mate, you should have warned us of "shocking pics"

id look for another tank but would prob do the electrolisys too, just to see if it can cope with THAT much rust without burning holes through the tank - yea, it might be just your tank paint holding the petrol in :shock:

do keep us posted if you take the electrical way :-D

[Nessism]

The Caswell stuff is THICK, good stuff but not what you are looking for based on what you stated.

Por-15 tank sealer is the defacto standard around here. Pretty good stuff but the job is only as good as the preperation.

Regarding your tank in general, if the entire inside looks like that photo, throw it in the trash and find a new one. Looking in through the petcock hole (put a flashlight shining in through the top hole first) will give you a pretty good idea what's it like in there.

Good luck.

[DMB]

Clean paint

So I guess I should have mentioned that the paint is flawless and it looks like the bike is only 2 years old. Still very shiny and glossy, the factory vinyl is still holding very very well, and there is only one tiny little ding in the tank. So if I don't have to repaint it I don't want to.

Pictures:









I know that the majority of the rust is only surface. I am able to stick my finger in the top hole and I am able to scrap of a good amount of the rust. The tank was stored with about 3 gallons of gas in it for about the past 5-10 years (from what I figure the last time it was run). I spent about an hour a few nights ago going over the whole tank and knocking on it with a penny and listening to how the metal sounds (trick I learned from my best friends dad while restoring a 1960 Ford Falcon in high school with him). The tank metal is near perfect.

So I think I am going to do a mild phosphate solution rinse with aquarium rocks first to knock of the majority of the rust hopefully (thanks Nessism). Then try the electrolysis on it and see what happens. If all else fails, I will just take it to a shop and have them dip and coat the tank and I will have to have it re-painted.

[DMB]

Regarding your tank in general, if the entire inside looks like that photo, throw it in the trash and find a new one. Looking in through the petcock hole (put a flashlight shining in through the top hole first) will give you a pretty good idea what's it like in there.

I haven't looked in through the petcock hole yet. Stupid guard on the inside of the tank won't let me get a flash light pointed down there. I have ordered one with a goose neck on it so I can. But this is how the petcock looked when I took it out (Also in another thread).

[Nessism]

I did a lot of work on my 550 tank bring it back into shape. If you shine a powerful flashlight into the main opening, there will be enough indirect light for you to get a pretty good look at the inside if you look in through the petcock hole.

The phosphate solution (EvapoRust is great stuff) will work but it takes several days and you need to rotate the tank. Hard part is sealing the tank off so it won't leak. I can post some photos later of my sealing solution if you can't come up with something.

Good luck.

[DMB]

The phosphate solution will work but it takes several days and you need to rotate the tank. Hard part is sealing the tank off so it won't leak. I can post some photos later of my sealing solution if you can't come up with something.

Good luck.

Sealing the tank I have figured out. What is the mixture of water to phosphate? 10-1 H2O to phosphate, 5-1? Also, all I have been able to find is TSP (Tri Sodium Phosphate). Is this what I want? Also, it the mixture harmful to the paint?

[catbed]

my tank was worse and i sealed it with KBS-Coatings.com tank sealer. its 36 bucks and comes with a cleaner, phosphoric acid, and a sealer that can seal up to 5 gallons of tank. its holding up very well.

[DMB]

Looking in through the petcock hole (put a flashlight shining in through the top hole first) will give you a pretty good idea what's it like in there.

Good luck.

Just did that and I am a little relieved. there was about 3 gallons of gas in the tank when I got it and the rust is only really bad on about the top 2 inches of the tank. Where the gas was in the tank it is rusty but not to bad. I still can see bare metal in some spots.

[DMB]

Phosphoric Acid

The phosphate solution will work but it takes several days and you need to rotate the tank. Hard part is sealing the tank off so it won't leak. I can post some photos later of my sealing solution if you can't come up with something.

Good luck.

So I have been having a hard time find phophoric acid locally. Can anyone point me to a local supplier or can I buy it online and have it shipped .

[Nessism]

Jasco Metal Etch and Metal Primer is basically the same stuff - phosphoric acid. Lowe's and Home Depot used to sell it but I haven't seen it for a while.

[nert]

I have used the electrolysis trick on tanks worse than yours. Works great!!!!. You would be crazy to trash that tank. I have no experience with sealing the innards afterward. I could use good advice on that.

TSP is what you want to use. Mix 5 tablespoons per 5 gallons of HOT water and mix well. Check your electrode regularly, i use coat hangers. Eats them up pretty quickly. I will change several batches of the solution over a period of 3 days. You should be delighted with the results. I have at my disposal several, (4) different battery chargers, tricklers, 12vdc power supplies, etc. Electronically, they are not the same. They all charge batteries, but not all of them would perform as rust removers.

The TSP solution should not harm good paint. It might slightly stain/brighten old paint. It would be wise to cover the paint and wipe any splash off anyway. Why chance it?

follow up photos please..