Question on using Evaporust

[Downs]

I need to take care of rusting in a recently acquired 82 GS tank. I've tried to search out some shops in the area that would be willing to tackle the task but haven't been able to find any that do that kind of work and the one that might has such low ratings and poor reviews I'm not willing to trust it to them. So looks like I'm doing it.

Evaporust has good reviews but it's looking like the tank needs to be completely filled for it to work properly. 6 Gallons of Evaporust is going to be pricey. Since this is a water based formula can you mix it with water? Can I pour in 2 gallons of evaporust and the rest water and it still be effective? The information on their website is quite vague on this subject.

Thanks,
Josh

 

[Nessism]

A couple gallons is enough. Rotate the tank and shake it every 15 mins. or so to keep the surface wet and you won't have any issues.

 

[chuck hahn]

5 gallons of 8% vinegar from wally world is about 10 bucks. And Vinegar wont eat any paint if its good and you spill on it. Can stay in there for a day or two without any worries.

 

[Downs]

CHuck I had read a few posts where folks were saying vinegar didn't help and actually made matters worse.

 

[Guest]

Video on using Metal Rescue on a gas tank:

Metal Rescue & Evaporust look to be pretty equivalent except Evaporust is also available as a gel.
One of the Velocity Channel car shows demonstrated using the gel on a vertical car panel. They used plastic wrap to keep the gel from drying out.


Both are available via Amazon Prime. You?ll save some $$$ by getting the 5 gallon size.

 

[Nessism]

If the paint on the tank is good and you plan to save it then Evaporust, or maybe that Metal Rescue stuff, is an excellent choice. If the tank is getting a full repaint I'd get something like Kleenstrip Etch and Prep which is phosphoric acid. You can use this stuff on a tank with paint as well since the phosphoric acid is safe for short exposure on paint, it's just that you need to watch the tank and take care of any seeping at your plugs or the paint job will suffer. Key aspect with any tank cleaning is to rinse well and be ready to dry out the tank quickly to avoid flash rusting. I like to dump some alcohol in the tank after rinsing and dumping out the rinse water. Swish around the alcohol and dump that out, then follow up with a good heavy blast of WD-40 to further help protect the metal. There may still be some light orange tinge to the metal but this will be minor and nothing to worry about.

Oh, and needless to say you need to fashion some good solid plugs for all the tank openings before beginning any of this. Don't rely on the petcock, fuel cap, and tank sending unit (if used) to seal the tank. Remove all the factory fittings and make something more robust.

 

[chuck hahn]

Vinegars never failed for me.

 

[Downs]

Well I bought 6 gallons of vinegar. Let's see how it works.

 

[alke46]

Well I bought 6 gallons of vinegar. Let's see how it works.

Be sure to post your results. It may be helpful to future tank restorers.

 

[chuck hahn]

My thing is once the zinc treatment ( or whatever it is ) that is used on tanks when they are made is compromised they keep being prone to rust unless you do a liner or keep it topped off. What I would like to see is a way to restore that original protection and have it still look like the original OEM metal surface.

 

[chuck hahn]

Use the 8% and if its rather heavy rust let it set as few days. I also got a wire coat hanger wit a loop bent on the end like gun cleaning rod. A Chore Boy steel pad works great for applying a bit of abrasive scrubbing to help clean things too. You get the idea.

 

[Nessism]

My prefered method is to add some aquarium rocks to the tank and shake violently because they are small and have sharp edges so they will reach into areas other methods won't. If using phosphoric acid like Etch and Prep it's generally not needed though.

 

[chuck hahn]

I have used nuts before. I always make sure they arte magnetic too. I use a extendable magnet to fish them out. But now the Chore Boy and wire seem to be just as effective and easier to do. I have even put a drill motor on the wire and whipped the scrubber around..that work pretty good too.

 

[Nessism]

No way to get into the corners and/or around the filler neck using your method chuck. And nuts and bolts are too large to get into the nooks and crannies too. That's why I went to sharp edge small aquarium rocks. Down side to that method is getting them all out. It's not easy and can take a lot of time. Many aquarium rocks are poly coated too so those don't work as well as uncoated rocks. I suppose none of this matters that much if you are going to coat the tank after derusting. I'm more looking at this from the standpoint of not coating afterwards unless absolutely necessary.

 

[chuck hahn]

End of the wire pokes very well into the rear corners and along the sides seams. I got my inspection mirrors to check. You gotta rinse the crud out a lot to inspect inside but then you know where you need to reconcentrate the efforts.

 

[Fjbj40]

Phosphoric acid is effortless, no mechanical action required. It dissolves and totally removes the rust. Follow up with water rinse with baking soda to neutralize, then IPA or acetone to dissipate the water, then coat with your choice of coating.

I would assume Evaporust or the other dedicated rust removers dissolve all rust?

 

[Nessism]

Phosphoric acid is effortless, no mechanical action required. It dissolves and totally removes the rust. Follow up with water rinse with baking soda to neutralize, then IPA or acetone to dissipate the water, then coat with your choice of coating.

I would assume Evaporust or the other dedicated rust removers dissolve all rust?

You don't need baking soda with phosphoric acid. I agree with the water rinse and IPA part, and some WD-40 doesn't hurt either, assuming you are not going to coat afterwards.

Evaporust is pretty amazing stuff. Only downside I've found is that it is expensive and has a limited lifespan. And speaking of lifespan...I've got a jug of phosphoric acid that has been recycled countless times and it still works fine. The sludge settles do the bottom of the jug and all you need to do is pour off the good stuff on the top. It can be diluted if you want and it will still work well, just slower.

 

[Downs]

ANy of ya'll have experience using the electrolysis method?

 

[Guest]

I used a gallon in my tank, swished it around and set the tank at different angles over a few days. Evaporust works slowly. Afterwards I strained it through a coffee filter as it can be re-used again. Rinsed with water and blew out the tank with compressed air and rolled up a sheet and fed it through the tank to pick up any residue. Evaporust becomes tacky so the sheet, compressed air and even a shopvac with a small diameter clear plastic hose attached to the hose with duct tape will do. As Nessism says, spray some WD40 in afterwards or it will flash rust.

 

[alke46]

I have only done 1 tank, but if I had it to do over then I would take it to a radiator shop and have it boiled out. After boiling, the shop could coat it with redkote. Not sure if that's the correct spelling but I have heard it is something that radiator shops do.

Good luck with yours and do post results.