tank cleaning

[Casper]

Hi OldRider2,

Both the rebar and the bolt should be connected to the positive lead and both be the Anodes, the actual tank itself should be the Cathode and connected to to the negative lead. This will draw the rust off the inside surface of the tank and then the anodes will collect the rust. I think what you did was just clean the heck out of the rebar. Not to worry, an easy mistake if you have not done this before.

Cheers,

[OldRider2]

Oops I obviously didn't know what I was doing and I misunderstood one of your earlier posts. When I read there should be two electodes and I looked at the previous pictures of a piece of metal in each opening of the tank in a previous post I thought the second electrode should be in the tank filler opening. I had the negative hooked to the tank at first and then moved it to the other opening when I added the bolt. I should have just added the extra metal to the sending unit opening. I will try this again, maybe this weekend, put in less soda, more metal and try it one more time. I never did take Chemistry! Better luck next time.

[scootsx2]

It won't be shiny. Mine was a dull gray but no rust or other crud anywhere. If you can scare up something like a dentist's mirror, use that and a flashlight to inspect the underside of the top of the tank to be sure you didn't miss any rust there. If you didn't have much buildup on the electrodes then perhaps you didn't have as much rust as some others. Were your electrical connections tight? Didn't you say you ran it on 6 volts? You can try 12 volts and see if you get any additional crud on the electrodes. At 12 volts the initial current through my tank was about 6 amps, gradually tapering off to about 1.2 amps.

Whoops, I just read the two previous posts. The two electrodes in my tank photos are connected in parallel to +12 volts. The tank itself is connected to ground. Yes, you "de-rusted" the rebar I think you will see dramatically different results when you get it wired up correctly.

[OldRider2]

Yeah but Scoots, it is one of the nices looking pieces of rebar I've seen! Between you and Casper I've got a mini CHEM101 introduction!

[OldRider2]

I started the cleaning/derusting process last night and it appears to be working better already. At the recommendation of my NGW Chemistry Instructors I only used the TBSP of soda per gallon, ground down a good clean connection on my rebar, added extra steel bolts/nuts, and checked all my connections. It was running 4-5 amps last night and had dropped to 2.5 - 3 amps this AM before leaving for work. This is a much stronger amperage than it was doing the first time. I'll pull it later today when I get home or tomorrow to see what it looks like. As long as I'm not to busy cleaning up the snow/ice storm we're getting!

[dritzman]

I'm going to clean my tank tomorrow using muriatic acid and naval jelly. Am I correct by assuming that I want to remove the float? If so, what is the best way to plug the hole?

[scootsx2]

I used a big rubber "cork" that I picked up at the hardware store. Lowe's has them in the trays with their "specialty" hardware.

[Casper]

I'm going to clean my tank tomorrow using muriatic acid and naval jelly. Am I correct by assuming that I want to remove the float? If so, what is the best way to plug the hole?

Yes you should take out the float, easy to do. I agree with scootsx2, a rubber stopper is a good choice to fill the hole so you can fill the tank right up to the top.

[dritzman]

Thanks guys

[dritzman]

Any tips on how to dispose of the acid and jelly after completion?

[duke182]

one way is to catch it and dispose of it down the drain.
you could catch it and let it evaporate and thenput the residue in the trash.
or incenerate it.
call your local sewer treatment facility or land fill and see what they have to say.

[ducmeister]

I work in the airline industry and we've used phosphoric acid gels for removing corrosion from aluminium for years. I've tried it on steel parts (not aircraft) as well and it works fine. It leaves a dark coating that is very stable and lasts for years.
Having said all this, I gave my tank a rough cleanout and then coated it with Red Kote. It seems to have worked well so far.

[dritzman]

I cleaned my tank today and WOW what a difference!! It was very easy to do and boy am I glad I did it. She was filthy!! I am extremely happy that I read this thread! Thank you everyone for sharing your experiences.

[terry_208]

Duct tape works good for sealing the sending unit hole when using electrolysis. Allows you to fill the tank with solution to the very top, but with only one electrode.

When I cleaned the tank on my '76, I believe I hooked the "+" to the tank and the "-" to the eledtrode. It seemed to work ok. I looked at the electrons flowing from "+" to "-", just as modern car's electrical system does(?). I'm going to have to try switching the wires on the next tank. It may work even better.

[Placerville]

When I cleaned my tank with Muriatic acid, it was still in the bike. I removed my fuel sending unit in order to clean it separately. I then sealed the tank sending unit hole with a piece of glass I cut and then sealed on with pure silicon. I didn't want to use metal for the seal as the only thing I had available to use was a can lid and I didn't want to put something that thin on the opening for fear that the acid might eat through. With the sending unit hole sealed, I could then fill the tank to the filler neck with acid. I agitated it with a wooden stick thought the neck for about 30 minutes. It was entertaining watching through my 'glass window' as the acid did it's thing. After draining the acid with a small plastic bulb pump, I filled and drained the tank 3 times with water. I then removed the glass seal. While filling the tank with water from the filler neck, I pumped it out through the sending unit hole. I did this for several minutes to make sure I had all of the dissolved material washed out. It came out looking like a brand new tank.