Topic: Gas tank Derusting

[thelowmax]

I feel like a shill fore this company but I'm not. I just really like a product that does exactly what it says it does. Evapo-Rust. Non-toxic, non-corrosive, biodegradable, water soluble, and REUSABLE!! I just fill up my tank, swish it around, and 24 hours later, i'm almost done. I'm not a fan of Creme Liners so I just rinse it out with water, then fill it with gas. I've done several tanks over the years and to this day they all look like I just finished cleaning them. When I'm done I just put it back into the bottle until I need it again. You can use it over and over. It works great! No wire brushes or scraping at all. Just rinse.

Let's see if I can get these pictures posted.

[thelowmax]

When I get home I'll post the completed tank pictures but as you can see, where the Evapo-Rust was there is no rust.  FYI, I did this in my bathtub and simply rinsed away the mess.  With no real odor, nobody even noticed.  And guess what the company recommends you do with the old Evapo-Rust that doesn't work anymore...  pour it into your garden! However, I don't recommend drinking it. It tastes awful.

[Cqyqte]

Vinegar is cheaper and you can reuse the dirty vinegar to kill weeds next summer!!! 

[thelowmax]

Vinegar does work and Evapo-rust does cost about twice as much ($20 a gallon), but for the time and effort involved, the latter is the way I go. Also vinegar loses it's power after saturation. Evapo-rust can be used over and over, so it's actually cheaper in the long run. Besides, when I use vinegar, everybody keeps asking me if I'm making pickles or something .

[MJL]

I was thinking about the vinegar route, it's $2-$3 a gallon and non toxic.

[thelowmax]

I'm already uncomfortable knowing that vinegar is used for food and feminine hygiene.  Besides, there are already too many reasons to yell, "douche!", as I ride by.

[Stev-o]

I just bought two gallons of vinegar, $1.98 each.  Plan to do my Yammie tank.

[Vinhead1957]

I endorse using Evapo rust also. Non toxic, reusable and it works!   I had only the gallon and I derusted the tank to my amazement.   Really like the product. I am currently soaking other parts in my house, with no harmful odors.

[seanbarney41]

I have tried Evaporust and it didn't do much for me...wonder what I did wrong

[thelowmax]

When I first tried it in my shop during the winter, it worked but not well and it took a long time. Then I tried it again during the summer outside and found  that it works much better when warm. The bottle even says to use it above 65 degrees. I bound some mufflers in heavy duty garbage bags, hung them from the rafter in my basement near the furnace and  then filled them up.  They were clean but the end of the day. Keep the item wet and warm and it will work wonders.  Jeez. they should be paying me.

[Stev-o]

Where are the "after" pics?

[goldarrow]

Don't we or most of us have battery charger? Water? Baking soda? Small piece of metal iron laying around I your shop? Time? Let's do electrolysis.

[thelowmax]

I'm still working on the tank and will post finished pictures soon. But in the meantime, I'm going to do a side by side experiment with vinegar and Evapo-rust. Stay tuned!

[Vinhead1957]

http://s906.photobucket.com/albums/ac270/vinhead/The%20Honda%20Project/?action=view¤t=DSC06463_zps6ac3694a.jpg&evt=user_media_share



http://i906.photobucket.com/albums/ac270/vinhead/The%20Honda%20Project/DSC06466_zpsaa82f3a9.jpg



Hard to get flash in that little hole

[MJL]

Ok. I'm not so sure about the vinegar. I bet it works great on chrome, but the stuff I have that I tried vinegar on had rust so bad that the chrome was flaked off. I used a toothbrush to work the rust off, and a day later I have surface rust. I was going to do this with my oil tank, but have decided not to now.

[trueblue]

Once you have finished with the vinegar, rinse it with water then coat it with oil.  It will stop the flash rust .

[Terry in Australia]

I tried electrolysis, but all it did was make all my hair fall out! I use Phosphoric acid, it removes light rust in minutes, and heavy rust overnight. It's not a dangerous acid, (it's used in the production of soft drink, or "soda pop" for my Seppo mates, so we've all drunk some) and it's cheap. Cheers, Terry.

[thelowmax]

So, ultimately, I was using the Evapo-rust and the tank was coming out great. And I have come to several conclusions concerning the pros and cons of it and vinegar.

Vinegar PROS- It's pretty cheap. You could fill an entire 5 gallon tank for around $5 or $10 bucks. This makes it pretty easy to just fill it and let it sit.

Vinegar CONS- It seems to take a looooong time and isn't as effective on the heavily rusted areas. These required scraping eventually and later some wire brushing.  The main reason I don't like to use vinegar (I was quickly reminded) is the smell. The process smells like rotten eggs. It stunk my whole apartment up.

Evapo-Rust PROS- 1. Just put it in and it works. It dissolves the rust and ONLY the rust. It wot harm the metal. It's non-toxic and non-corrosive. environmentally friendly. It's reusable. What little smell there is, is not offensive at all. Due to space constrictions, I do a lot of my bike repairs in my apartment, so odor counts.  Ultimately, I think it does a better job in the end.

As for the tank I was working on... it developed a leak in the front corner. It had rusted through at the seam and only started to leak in the final stages of the process. Closer inspection of the outside showed that a chip or two had turned into a rusty spot right on the seam. When the inside met the outside in the middle, it was all over. It's a shame too because the outside actually looks pretty good.

Anyway... Can I weld that? JB Weld and seal it? Or should I chalk it up to experience and just get another tank?

Evapo-Rust CONS- The only con is that it's costly. Because of this I couldn't fill the tank to the top and had to keep rotating and shaking it.

[thelowmax]

Here's the inside and outside of the tank where the hole is. The seam is rusted and you can see the pinhole on the outside in the almost center of the pic.

My first inclination is to just JB Weld the hole and seal the tank but another tank might be easier and cheaper at this point. What do you think?

[Terry in Australia]

Get the POR-15 kit mate, and if you don't know anyone who can solder/braze the hole up, JB weld it first (do a good job, make sure you remove all the old paint/rust from the affected area first) then seal it with the POR-15.

The POR-15 kit comes with it's own little bottle of phosphoric acid, so you could have saved some money and just bought the kit in the first place. Cheers, Terry. 

[Stev-o]

My vote goes for vinegar for all except the worst rusted tank. Just did mine and am very happy with the results...

[Terry in Australia]

Nice tank Steve! Vinegar is good for light rust, but it's pretty useless for cleaning it back to a completely rust free state. For that you can't beat phosphoric acid, and if you're careful you can use it without hurting your paintwork. Cheers, Terry.

[trueblue]

Plumbers solder is great for fixing pinholes, I did mine over 2 years ago and it is holding fine without a liner .

[Terry in Australia]

Plumbers solder is great for fixing pinholes, I did mine over 2 years ago and it is holding fine without a liner .

Yep, I've soldered them too, but I like POR-15 as added insurance, if there's rust holes present, there might be some other paper-thin areas that I've missed.

[Stev-o]

Nice tank Steve! Vinegar is good for light rust, but it's pretty useless for cleaning it back to a completely rust free state.

Agreed, and the RD tank only had light rust. Plus, I did not want to take any chances screwing up the paint on this one with a stronger acid.

[fendersrule]

I plan on using the vinegar method since my tank only has light rust.

Then, I'd do a good amount of rinsing afterwords.

but how exactly do you "oil it up" inside to prevent flash rusting? Let me know your exact process, because I'm going to have to do it soon!

[Terry in Australia]

Once you've rinsed the tank thoroughly, dry it out as best you're able (a litle methylated spirits tipped in and swished around will help) then once its dry, a small amount of a thin oil (two stroke oil, ATF etc) tipped in and swished around will prevent it from further rusting, and won't hurt your engine. Cheers, Terry.

[fendersrule]

How much is a small amount? a half of a cup?

It seems that even with a half of a cup, there is no way that you're going to get oil to cover all of the steel in a '78 CB750 gas tank. There are so many baffles/reservoirs that I would be doubtful. But I could be wrong.

[Cqyqte]

I spray the inside surface of the vinegar cleaned tank with a can of "Fogger" an marine engine winter prep product (oil and rust inhititors).  Works great and doesn't mess up the carbs.

[Terry in Australia]

How much is a small amount? a half of a cup?

It seems that even with a half of a cup, there is no way that you're going to get oil to cover all of the steel in a '78 CB750 gas tank. There are so many baffles/reservoirs that I would be doubtful. But I could be wrong.

Yeah mate, you're wrong. There are no baffles in any CB750 tanks (I've cut them all open at one time or another) so tip in a cupfull of two stroke oil or ATF, swish it around thoroughly, and it'll coat every nook and cranny in your tank, then just drain off the excess. The other benefit is the oily fumes will fog your exhaust system with an oily mist, preventing it from rusting out. Cheers, Terry.

[MJL]

Once you've rinsed the tank thoroughly, dry it out as best you're able (a litle methylated spirits tipped in and swished around will help) then once its dry, a small amount of a thin oil (two stroke oil, ATF etc) tipped in and swished around will prevent it from further rusting, and won't hurt your engine. Cheers, Terry.

When I fixed my oil tank I put water in to make sure it didn't leak, then put it in the oven at 250 for awhile to evaporate the water.

[CROMOLY]

So, ultimately, I was using the Evapo-rust and the tank was coming out great. And I have come to several conclusions concerning the pros and cons of it and vinegar.

Vinegar PROS- It's pretty cheap. You could fill an entire 5 gallon tank for around $5 or $10 bucks. This makes it pretty easy to just fill it and let it sit.

Vinegar CONS- It seems to take a looooong time and isn't as effective on the heavily rusted areas. These required scraping eventually and later some wire brushing.  The main reason I don't like to use vinegar (I was quickly reminded) is the smell. The process smells like rotten eggs. It stunk my whole apartment up.

Evapo-Rust PROS- 1. Just put it in and it works. It dissolves the rust and ONLY the rust. It wot harm the metal. It's non-toxic and non-corrosive. environmentally friendly. It's reusable. What little smell there is, is not offensive at all. Due to space constrictions, I do a lot of my bike repairs in my apartment, so odor counts.  Ultimately, I think it does a better job in the end.

As for the tank I was working on... it developed a leak in the front corner. It had rusted through at the seam and only started to leak in the final stages of the process. Closer inspection of the outside showed that a chip or two had turned into a rusty spot right on the seam. When the inside met the outside in the middle, it was all over. It's a shame too because the outside actually looks pretty good.

Anyway... Can I weld that? JB Weld and seal it? Or should I chalk it up to experience and just get another tank?

Evapo-Rust CONS- The only con is that it's costly. Because of this I couldn't fill the tank to the top and had to keep rotating and shaking it.

Hi,
 have you ever tried molasses?
Works wonders, smells like beer,  gets in all nooks and crannies, does not arm paint or  chrome and is ok for the environement ... But it shure is nasty on rust,
For 20$ worth of molasses and a kid's pool you could dip a hole bike and get it rid of years of rust...
I use 5 water to 1 molasses and it really works great.
The only down side is how long it takes.
From 2 to 4 weeks depends of how bad the parts are.
À+
Crom.


Cromoly.

[Terry in Australia]

Once you've rinsed the tank thoroughly, dry it out as best you're able (a litle methylated spirits tipped in and swished around will help) then once its dry, a small amount of a thin oil (two stroke oil, ATF etc) tipped in and swished around will prevent it from further rusting, and won't hurt your engine. Cheers, Terry.

When I fixed my oil tank I put water in to make sure it didn't leak, then put it in the oven at 250 for awhile to evaporate the water.

Yeah mate, that's a good idea if you can fit it in your oven, otherwise a heat gun works wonders too. Cheers, Terry.

[Retro Rocket]

Once you've rinsed the tank thoroughly, dry it out as best you're able (a litle methylated spirits tipped in and swished around will help) then once its dry, a small amount of a thin oil (two stroke oil, ATF etc) tipped in and swished around will prevent it from further rusting, and won't hurt your engine. Cheers, Terry.

When I fixed my oil tank I put water in to make sure it didn't leak, then put it in the oven at 250 for awhile to evaporate the water.

Yeah mate, that's a good idea if you can fit it in your oven, otherwise a heat gun works wonders too. Cheers, Terry.

I wrap a rag around an airhose and blow air into the tank while submerging it in the sink, no need to dry it out....    And before anyone says "you could burst a seam doing that", the rag lets air seep past while adding enough pressure to find any leaks....

[Terry in Australia]

two seperate issues Mick, I was talking about drying it out, but anyway, your test method is fine, I made a plug for the cap hole so I could pump in say, 10 psi (it has a gauge attached) then I can just submerge it and see where the bubbles come from. Cheers, Terry.