What grade Walnut shell needed for interior fuel tank cleaning.

[Magic]

Hey guys and gals, The inside of fuel tanks has a light rust covering nothing harsh or flaky. The outside paint is perfect and don’t want to change that for sure. I’ve read about wrapping the tank in thick blankets taped so they don’t unravel and placing it in the clothes dryer acting as a tumbler on cool no heat of course. Making sure that the tank wrapped in blankets doesn’t move about while tumbling with my choice walnut shells. There are of course different sized shells or media grade. Would coarse shells that are said to not damage metal or a finer walnut shell grade? These tanks sat empty for 5 years in a garage. When I rub my finger inside as far as I can reach lol I get smooth rust color easily with no hard edges at all. The inside of the tanks are not completely covered in rust color about 50/50. Any experience out there or other advice outside what I mentioned to clean them up inside is appreciated. Thanks, Merlin

[chuckthebeatertruck]

Walnut shells won't work for what you want to do. They need to either be driven (air blasting) or in a vibratory tumbler. Simply spinning them over in tank won't do much. I've done thanks for HOURS in the dryer with actual tumbling media and barely hit the rust -- walnut shells won't do anything and will leave a mess of dust and crap to clean out. They really are a very poor choice for this application.

Also, I would personally never, ever, ever put walnut shells in any fuel or oil tank. It can be nearly impossible to get all bits of shell out. They will swell, they will get stuck somewhere and they will be a PITA.

I haven't read about this blanket and dryer thing . . .I've done it more than once:

https://forum.antiquemotorcycle.org/...736#post286736

If you have perfect paint; consider vinegar. Cheap, very effective, won't damage paint.

Simply fill the tank to the brim with vinegar. Leave for a few days, rinse with VERY hot water and immediately slosh WD40 around to stop flash rust. You'll have a completely clean tank and no paint damage at all.

[indian301]

Go to the store and buy some citric acid used for canning. Mix 3-4 oz with 1 gallon of warm water. Pour in the tank and let it sit for a day. Rotate the tank on each side . Continue doing this until all of the rust is gone. Flush out the tank with baking soda and water. Let it dry. Will not harm the paint .

[jim d]

I would not put a tank with good paint in a clothes dryer and let it spin. No matter how well you have it wrapped in blankets. Something unexpected could happen and cause something to rub through the paint or cause a small ding. The most unexpected things happen when you least expect them. Lots of other products to put in the tank to remove light rust that won’t damage your paint. Sounds like vinegar would work fine for your rust issue, Why take the risk of having it spinning in a dryer.

[Magic]

I appreciate the replies so far and am in no rush at all since protecting the exterior paint is foremost. I’ll highly consider the acidic vinegar or citric acid as I use vinegar to clean other metal surfaces at times. Certainly test on the backside underside of tanks first to assure myself. The spinning dryer scenario would have been a tightly package tank not able to move at all, bubble wrapped and taped packed inside blankets. Any further suggestions and advice is appreciated. It’s not really bad inside at all as it’s surface dust rust I don’t want diluted in fuel even with a filter inline.

[otis71]

Evaporust available at Home Depot (Lowe’s has an equivalent by another name) works very well and is non corrosive. Vinegar works too but should be neutralized afterwards and leaves flash rust issues. Evaporust works best at warmer temperatures so leaving in the sun speeds things up. Another benefit is it can be used over and over but eventually loses potency. Not terribly expensive either.

[vph-d]

I've had good results with Evaporust, it works better than vinegar.
vph-d

[marksg]

Agree on Evaporust. II use it a lot on many different parts to remove rust. Also available @ Harbor Freight.

[KNUCK]

I actually put a large hand full of screws, nuts and bolts in the tank with a little gas or WD 40 and start shaking by hand. I do it off and on for a few days and things really clean up nice. Flush out with gas thoroughly and ready to go. As yours is not really that bad so should be an easy clean up.

[T. Cotten]

I actually put a large hand full of screws, nuts and bolts in the tank with a little gas....

Bless your heart, Knuck!

I bet it took out dents, too.

....Cotten

[KNUCK]

Good old American steel is too tough for that to happen!

[T. Cotten]

I actually put a large hand full of screws, nuts and bolts in the tank with a little gas....

I bet it took out dents, too.

Good old American steel is too tough for that to happen!

Knuck didn't get it, Folks.

He's lucky he didn't get the Darwin award using gas.

....Cotten

Darwin-Award-I-warned-you.jpg

[KNUCK]

Folks, I got it. Gadfly, Thanks but since I didn't meet the criteria for this award I guess you are stuck with it.

[Magic]

I’m going to use the Evapo Rust as I got 2 gallons at Harbor Freight for under $60.00. I was going to go with just one gallon however 2 will almost fill one of the 2 1/2 gallon tanks and I won’t have to turn them as often. It says on the label doesn’t harm good paint which I’m going to do my best not to let it get on the exterior if possible. Thank you everyone for setting me straight with the walnut shell packed tightly in the dryer scenario. Ride on.

[otis71]

The label is correct. Don’t worry if it gets on the paint. It’s also biodegradable and can be poured down the drain.