More on Kreem removal (UPDATE)

The Z1R "Get the Kreme out" gas tank saga continues.

Went to a buddy's body shop today and spoke to his crazy painter (aren't they all?)

He gave me a tin of MEK (methyl Ethyl Ketone) and warned me that it is powerful stuff.

When something comes in a tin and it's all warning labels you know it's potent.

Careful to have the tank well plugged (and I did this outdoors) I used a metal funnel to put in about a pint and gently turned and rolled the tank for about 10 min.

Drained out a liquid that looked like milk!

The stuff is no doubt eating the Kreme (BTW I already have 90% out... it's the last pesky stuff I'm trying to remove)

Did it two more times and it came out less white each time but that was it for the MEK (I only had a quart if it)...

WARNING! This stuff gasses out and EATS RUBBER! You have to be very careful and thankfully the bottom petcock has a 3/4 inch drop tube that makes draining relatively easy.

The tank still showed lots of flash rust so I gave it a short vinegar bath and the then blew it out with a compressor.

The rust still shows so I put in a full bottle of Evaporust (a product sold here in Canada that is supposedly very safe)

Going to leave it for at least 24 hours.

I took a peek in the filler cap and there is still some pesky Kreme left in there but it is no longer white but rather dark brown... It appears the surface was eaten by the MEK.

I was hoping this was the end of it but I think I might need more MEK which is hard to come by here in Winnipeg. I got a tiny whiff from a few feet away and it is deadly smelling stuff that is sure to kill brain cells by the million.

I'll try to find a gallon of the stuff and repeat the process till I can no longer see any of the crap in there.

Then I will take another stab at the final rust removal.

Gary said he used Oxalic acid in powder form and the pictures he posted look amazing. That will have to be the final touch. It's wood bleach and the results he got are nothing short of amazing.

I'll be ready to write a book on this tank when I'm done. "Tanks for the Memories"

I really wish I could find a product that inhibited rust after its removed as I fear the galvanizing has been completely removed with all the vinegar, MEK, Sea Foam, Car wash baths and not to mention the fact it was probably already corroded many years ago when the idiot I bought the tank from decided to Kreme it. It is not my original tank but rather one I bought 15 years ago, and painted not knowing it had been lined)

After the last of that crap is out I want to prevent the return of the flash rust.

Someone suggested rolling lead shot around in it to coat the inside? Sound interesting.

After 32 years I am not going to rush the tank. I want it to be pristine clean as I do not want the petcock and carbs getting contaminated again.

Wayne

Where did you get the Evaporust at? I'm in B.C. and I don't think I've seen it around.

Nevermind, uncle google tells me Crappy tire carries it.

I know a lot of guys in the states take their tanks to the radiator shop and have them dipped. I used Evaporust on mine with a sealer but it was not enough. I bought a Spor15 motorcycle kit. The stuff works awesome to coat the inside. Its a 3 part system. A cleaner, surface prep and the sealer. Just be sure to get it where it belongs the stuff does not come off easy once it dries.

Can't dip... The bike has pristine paint.

That sealer in the POR 15 product is a liner... No thanks.

Some people swear by them... most people swear at them.

I would never use one unless the tank had holes and in that case I'd source a new or different tank.

W

Here's a suggestion from another forum:

650king
*****
Re: how to stop flash rust in fuel tank and a bit more
« Reply #8 on: June 21, 2012, 12:37:48 PM »

I recently used plain undiluted vinegar full right to the top then stopped up for a few days... emptied half out and stuck a lightweight chain in there and then sloshed that around by hand for a few minutes... drained it all out then neutralized with a baking soda water mix (2 gallons) for about 5 minutes then flushed with clean water by hose nozzle - my final step was force drying it with a heat gun until no water dripped out then sloshing around 2 quarts of kerosene = no flash rust.

All of that can be done without harming the paint except the heat gun... if I wanted to protect the paint I would only use a hair dryer at that point - less risk to overheat the metal.

After rinsing with water try four or five bottles of dry gas. Shake it so it coats the inside of the tank. It will evaporate all the water and prevent rust from starting. If you don't get it all out it won't hurt anything. It has to be done immediately after the water is drained.

Found more MEK... at a concrete restoration place. They sold it quarts @ $12 per... Still no luck finding the Oxalic acid (bondex, wood bleach) I wantto try that for the final rust removal.

Scroll down on this post to see what a fellow member has to say about using the Oxalic acid: www.kzrider.com/forum/6-paint-a-bodywork...-horror-story#530002

The Evaporust is also working nicely but it must soak... I left it on its side last night, and checked it in the morning and there was a poker-straight line where the ruast was completely gone where it was immersed in the product. It just seems to consume the rust and yet does not change color like vinegar. It reamains the same urine yellow it is when in the plastic bottle.

The stuff is too expensive to fill the whole tank so will continue turning it.

Thanks for all the tips guys!

keep 'em comin'!

W

Once rust starts it will never go away without sealing it. Without a sealer of some sort you will go through this process every year. I would suggest running a real fuel filter to protect the carbs.

Got the rest of the Kreem out with MEK... then used a product called Magic Acid to remove the rust.

It turned a glorious silver metal color. Put more MEK in it to clean and dry out the chemical... then put some gas in it to try and seal it...

6 hours later the entire inside is rusted again.

Have one more product to try (a salt based acidic cleaner called LC-6799 by Lynx) Have a gallon of it and will try it out.

Unable to find Oxalic acid anywhere in this ditch-water town and the Lynx came from a concret company that swears it is a real rust eater and inhibitor. We'll see.

If that doesn't do the trick then I guess I'll have to break down and line the damn thing.

This tank obviously has all galvanizing gone and has somply become a rust factory.

Frustrated to no end.

W

I found this, regarding using modern fuels containing ethanol:

If your car was built in the before 1980, it may have a lead coated, steel tank. The water in ethanol could cause these tanks to rust on the inside. The government mandated that all gas in the USA contain 10% ethanol to help reduce tail pipe emissions. In the 1980s, automakers made vehicles with fuel systems to be ethanol and rust tolerant. Gas tanks began to contain polymers and Teflon which are extremely durable.

Could try a rust removal product that contains phosphoric acid as the primary ingredient, which may remove the flash rust (after muratic acid, for example) and inhibit further rusting.

Good Fortune!

I derusted a flathead V8 crankshaft in a molasses bath & had the same promblem. When I washed off the molasses it started to flash rust almost straight away. I was told to try soaking it in Washing Soda, so after derusting again I did & no rust! I have left it sitting next to my bench as as a bit of an experiment to see how long it would take for the rust to take hold again. Nine months later & not a sign of any rust!
In Australia it goes buy the name of Washing Soda or Soda Crystals. The only difference is the finish of the soda. Washing Soda is a powder & Soda Crystals are suprise suprise crystals. The product is actually Sodium Carbonate. Here it is available in the cleaning products aisle of the supermarket & is very cheap at about $2 a kilo. It is also extremely same & environmentally friendly.
Here is a link to the Australian brand so you can read about if you wish -
www.lectric.com.au/lectric_soda_crystals_u.html