TOPIC:

bluej58 wrote: Test

This is a great comparison of the different chemicals including the ole "coke" rust remover myth. I have also heard of molasses being used, but he didn't even include that myth in his tests.

I have also used electrolysis too, and while it does work, it produces toxic gasses and "hydrogenates" the steel and supposedly makes it brittle. Much like plating processes. It also takes the paint off if you submerge the tank in the solution.

I have also used Metal rescue in a gas tank, and it does work, and also will not harm the paint. I think you could drink the stuff. lol It seemed to turn aluminum into a goo, so I would avoid leaving any petcock in the tank. I also remove the gas cap and use a expanding rubber "freeze plug" type stopper. The small screw holes for the gas cap get plugged with a screw / o-ring. I made block off plates for the fuel sender and petcock for my old kaw. I actually have wrapped a tank in a sleeping bag and packed it into a dryer and ran it a few times Turning it around to reverse the rotation to remove all of the crud inside. I did this with MEK (liquid death, forget rubber gloves, they disintegrate in the stuff) with some small screws in the tank to remove one of those nasty "kreme" coatings that sealed the rust and junk in, rather than removing it. I feel the coatings are just another snake oil that covers up a problem, rather than actually fixing the problem. Coatings will fix small leaks, and I prefer to limt them to that use. It takes some talent to make a coating work and coat evenly inside a tank for sure.

My Kaw had been creamed, but it is all just a bad memory now.





I did not catch all of the prices he named off, but at ~25 bucks a gallon, metal rescue is definitely not a cheapie, and seems mostly ineffective after it is used once. At least it can be poured down the drain safely, instead of having to find a toxic waste disposal site. Like he mentions, it will not harm the paint.

This is a Honda VT600 tank I cleaned for a friend. As you can see, the paint needed to be saved, and It is still just this nice.



1997 Honda VT600C



Electrolysis will do some major metal damage too, especially if while in a hurry you accidentally reverse the polarity. Never mind how I know this. duh. lol

We've got stuff called bio rust over here, not sure if its available world wide but it comes as granules,. Fill the tank with hot water add granules to the strength in the instructions, leave for a few hours and tip out. Dry the tank with a hair drye r or leave to dry out naturally. Works really well. Only advisory I would add is to flush the fuel tap through with fresh fuel before fitting fuel pipe to carbs.

If you have some corrosion in tank do you need to stop it or can you just fill the tank complete full in the winter and drain the carbs...
So if you don`t have problem with rust in the gas... going into the gas filter...blocking it... then you don`t need to do anything ?

Or is like the gas tank will be eaten up quick if you don`t do anything ?

gordone wrote: If you have some corrosion in tank do you need to stop it or can you just fill the tank complete full in the winter and drain the carbs...
So if you don`t have problem with rust in the gas... going into the gas filter...blocking it... then you don`t need to do anything ?

Or is like the gas tank will be eaten up quick if you don`t do anything ?

If there is corrosion in the tank then loose debris will break loose and go down into your carbs. A filter can be installed but the type of filter appropriate for gravity fed fuel systems (no positive fuel pressure) doesn't filter very fine - they are more of a screen than a filter. I'd remove the tank, drain it, and derust it.

I see many in Norway use a tank sealer epoxy based paint, is these something you reccomend?

gasolin.no/por-15-tank-sealer-for-bil-1.html

Or is It toger metode better to use, I want a long term solution...?

gordone wrote: I see many in Norway use a tank sealer epoxy based paint, is these something you reccomend?

gasolin.no/por-15-tank-sealer-for-bil-1.html

Or is It toger metode better to use, I want a long term solution...?

That is a sealer. clean that crap out and forget the por15 garbage. I think this has already been mentioned. It is also extremely hard to get it to coat evenly. 595 SEK in USD = $ 72.6971. Spend that money on rust dissolve bath .

Agree with old_kaw, unless the rust is really bad, skip the sealer. Just derust. If you can find some phosphoric acid that's the best stuff. Just be sure to make some proper seals for all the tank openings before beginning the process. Phosphoric acid (same stuff as the Por-15 Metal Prep) is the stuff paint shops use to derust and clean metal. It's relatively mild and can be diluted, it just woks slower. Key thing regardless of what method you use to derust is to be ready to dry the tank quickly after rinsing. Have some isopropyl alcohol on hand to help dry the tank quickly. I use IA first and then quickly follow with WD-40 to protect against flash rust.

Nessism wrote: Agree with old_kaw, unless the rust is really bad, skip the sealer. Just derust. If you can find some phosphoric acid that's the best stuff. Just be sure to make some proper seals for all the tank openings before beginning the process. Phosphoric acid (same stuff as the Por-15 Metal Prep) is the stuff paint shops use to derust and clean metal. It's relatively mild and can be diluted, it just woks slower. Key thing regardless of what method you use to derust is to be ready to dry the tank quickly after rinsing. Have some isopropyl alcohol on hand to help dry the tank quickly. I use IA first and then quickly follow with WD-40 to protect against flash rust.

While I agree with Nessism MOST of the time, I believe the next time I clean out a rusty tank, I would like to try the Eastwoods rust remover shown in the video if I can find it locally.

Metal prep and phosphorus acid are an acid, and not really environmentally nor novice friendly. For >professional use only< I think it will also ruin the paint, but don't quote me on that one. I have used POR-15 and specifically "metal prep" and actually have some here in my workshop. Metal prep is more of a chemical "etching" agent and light rust remover IMO.

Gas tanks usually have rust caking and scaling inside and although the paint is normally already ruined on a rusty tank, it is best to strip the paint separately. You can also get by with only 1 gallon of Metal Rescue (or whatever you choose) by putting a plastic bag into the tank before filling , then fill it with water to take up part of the volume, and then add your rust agent after the bag takes up the extra space. I haven't tried this, since it seems too messy, and I do a lot of this stuff on my kitchen table, and have OCD when it comes to a nasty mess.

Check out this video, pretty painless stuff and no acid to neutralize with sodium bicarbonate:



This is a 86 honda CMX450CM gas tank that I cleaned up a few years ago. This one was hard to seal the filler neck with an expanding rubber plug. I used a small square piece of rubber to fill the gap.



Another no title , no keys, locked up tight. Notice the carbs off.. this is how it sat outside for at least a year before I got it. He had a rag stuffed in the carb holders, but then it sat with nothing over it in the elements (was my neighbor). This was a nut and bolt rescue too. This pic was taken the day I got it. Notice the masking tape gas cap. There are some real rocket surgeons out there that own DEAD bikes.



I told him he should at least cover it up, but he said he had a rag in the ports so it would be fine.. NOT! lol I had to break the cam to get the head off.



This motor had 450 miles, I bought it from a guy that answered an ad, but had to drive to Memphis to pick it, and a bunch of other parts up for the restoration.



And the final assembly.



A few parts I bought in Memphis. The frame was some sukzuki that went to the scrap man after I took that new motor out of it.



And it's ALIVE! Off to get a title in Jeff City. Easy peasy!

I've used all kinds of different derusting chemicals over the years and I've come to prefer phosphoric acid. It doesn't need to be neutralized, it's relatively safe, it can be recycled and used again and again, it's cheap and available at places like Home Depot. Evaporust is my favorite price be damned, but it's definitely more money and doesn't work as fast or as long before it goes bad. I've never used metal rescue.

Nessism wrote: I've used all kinds of different derusting chemicals over the years and I've come to prefer phosphoric acid. It doesn't need to be neutralized, it's relatively safe, it can be recycled and used again and again, it's cheap and available at places like Home Depot. Evaporust is my favorite price be damned, but it's definitely more money and doesn't work as fast or as long before it goes bad. I've never used metal rescue.

I need to try this stuff on a gas tank someday. I have heard good things about evaporust too, but have never tried it. Like Metal Rescue, it is pretty pricey by the time I drop 100 bucks on 4 gallons to fill the tank to the brim. I buy metal Rescue at Home Depot.

I have cleaned up several extremely BAD gas tanks, the worst being this XS1100SG tank I did years ago. I did electrolysis on that one.. When the rust relocated to the sacrificial metal, several holes opened up. One of the few times I have used JB weld to repair a tank, but it held up. Rusty sheet metal is usually too thin to weld or braze.

There were a few pinhioles around the mounting bracket, and to the left of the petcock locations in the "dip' at the tank seams.

Kleenstrip Metal Prep at Home Depot for $16/gallon. Dump it in a tub, drop in your tank, fill up tub with enough water to cover. Use two gallons of the MP if in a rush. It will eat off all that rust post haste and leave the tank sparkling clean .

If there are holes thru the metal I advocate tape on the outside to plug them and then use Caswell's tank sealer. Caswell's is THICK, almost like cold honey. It will reinforce the metal wonderfully.

A big soldering iron and tin is the ultimate weapon to close pinholes.