As the topic description states.

I have a really nice/restored tank that will go into my 914 that has been sitting for 7 years. The old tank is probably not salvageable.

I restored the outside surface of a totally clean interior tank a couple of years ago. Sealed all ingress and egress points with plastic wrap and stored it inside my house (basement - humidity controlled).

Yesterday I decided to install the new sender and all seals. Shined a light into the tank & spotted 4 or 5 spots that had oxidized (about the size of a quarter each). So, before buttoning it up.....should I worry about these? Would common acetic acid neutralize these spots?

I will not POR15 this tank.

Thoughts?

BTW, I need the nipple-to tank seals (fiber?).

Well you could use Redkote or I just purchased a 2 part epoxy for the inside of gas tanks.

http://www.caswellplating.com/restoration-...ank-sealer.html

Hope this helps

David

I pulled my tank a year ago to have it blasted and powder coated. I also used POR-15 with great success.

The hardest part I had was finding the two crush washers for the outlets. I looked everywhere - McMaster-Carr, Tacoma Screw, the industrial surplus store, Fastenal. No dice.

I never did find any, but I did happen upon a nifty solution. Go to a leather goods store and buy two hollow leather punches. One for the outer diameters, and another for two inner diameters. I don't remember the exact sizes but the 8mm (5/16") is the only inner diameter that comes to find. Just pull out your caliper and measure what you have now. I bought a whole kit of punches that included the sizes I needed.

Obviously, you won't be using leather gaskets. But the punches are good enough to punch a thin sheet of copper or aluminum from a hardware or hobby store. DIY crush gaskets. Punch the outer diameter first then carefully center and punch the inner diameter. I used a 16oz hammer. This method made perfect gaskets that have never leaked (I checked very recently).

Anyway, that might work for your gasket needs.

-marcus

Interesting! May try that

I got the nipple seals from Robert.

http://www.914world.com/bbs2/index.php?showtopic=110158

Racer Chris most likely has them as well.

DAvid

Yeah, it will, but like other acids when they encounter rust, what is left is an iron salt substance (in the case of acetic acid it will be iron acetate - not sure what this looks like to be honest). Phosphoric acid has this issue as well, leaving behind iron phosphates (white powdery film). Both examples are insoluble in water, so they won't wash away easily, but dishsoap and some elbow grease should get rid of it for you, for small amounts like you're talking about.

If you don't want salts that can't be washed away by water, other acids like sulfuric, hydrochloric, and nitric acids will all work very well and generate iron salts that are water soluble and will rinse away. In the case of sulfuric acid treatment, a non-toxic water-soluble iron sulfate salt is produced. Recommend using dilute sulfuric acid, not the concentrated stuff. Hydrochloric (aka muriatic) acid and nitric acid come with their own hazards and difficulties. I wouldn't recommend them for casual rust removal.

Good answer. Be careful of them all but be especially careful with sulfuric acid. It is a very strong acid and has oxidizer properties as well. When added to water they will heat up the water, again sulfuric does this especially. That means when added to a large volume of water you are fine, but adding the acid to a small volume of water can get hot enough to boil. The most extreme example of adding acid to a small amount of water is adding water to acid - DO NOT do that. The small initial volume of water can be turned to steam and blast you with acid.

Sorry, I have a lab and have seen a few accidents with stuff.

The fibre washers for the inlet and outlet are available at the bughaus. Cheap, and proper.

I REALLY need to proof my posts before sending!

I meant to ask about the use of acetic acid (vinegar) on the INSIDE of the tank, to remove minor oxidation after a total boilout and restoration of the tank's exterior.

Man, I hate getting old! Sorry.

Sure it will still work, but what I said still applies. You will end up with iron acetate which is not water soluble. So it will be hard to rinse off. Inside the tank I would not worry about it too much though. It probably won't harm anything in the engine or fuel delivery system since there isn't much of it, but I don't know for sure. Acetic acid in household vinegar is pretty darn dilute, so it'll take a while to get the rust reacted. Probably an overnight soak at least.

Pat maybe slosh around some POR Marine Clean with hot water in the tank. Then flush it with cold water. Then use the POR Metal Ready. Again flush with cold water. To prevent flash rust, dry it out best you can with paper towels, then stick a hair dryer inside the top hole and bake it. Did that with several tanks, and had no issues. Word of caution, the POR products may effect the paint. Be cautious when you do it, and have the garden hose ready. Your not put a coating inside the tank, only cleaning it with these two products. The Metal Ready will leave a very thin layer of zinc and eat away the rust.

I'm probably being anal about this. The oxide film is minimal at best, and I'm certain this amount of oxidation is in most tanks. The sock should capture anything that moves. My sock is not new, but I've cleaned it and it's as good as knew, so I'll just move forward.

The nipple gaskets are a bigger concern, as mine are destroyed.

This is an odd coincidence I have the same exact issue. Was looking for answers... my tank is also nearly perfect on the inside besides a 2" area of light oxidation. I wouldn't call it rust, per say... just a discoloration slight corrosion. I was wondering how to treat it. I want to avoid total POR 15 job on this since it is 99% good.

Also: need a kid with skinny arms to reach in there and sand off the corrosion! My g/f is able to do it but she's not that into it..

Here is a poor picture of the discoloration.. its not even really "rust" about 2 1/2 " long..

Click to view attachment

So really probably dumb question. I just pulled my tank and their is a lot of stuff inside it. However, I can't get the gas cap off - is there a secret?

Pat the local flaps sells a product called evapo- rust. You submerge the area overnight and brush it off in the morning. If I recall removes the rust through chelation? Won't hurt non oxidized metal or paint