Fuel tank rust removal

[sleeper]

moose-

I'm familiar w/the Dryer procedure...It works real well.

Timing IS critical however, as you posted "make sure your wife is not at home" Or comes home un-expectedly early !!!
How true that is !!!

[Cotten]

I recycle aquarium gravel because of its hard sharp edges; road pea gravel is often too rounded, and much of it is soft and turns to mud.
To scrub out the last abrasive particles after a final acid flush, I tumble with a slurry of cracked corn and baking soda. The corn gets sticky and makes everything easy to hose out. And don't forget some WD-40 real quick at the end.

MY apparatus is entirely dumpster scrap:



It took six sheaves to pulley down to about a rev per second. In theory it should eventually polish the insides, but I have let tanks run for several days 24-7 without penetrating some scales.
The worse have been rust and pits that were 'sealed' by ancient fuel turned to a resilient (and stinky) 'varnish'. The tanks required digestive solvent treatment even before abrasive tumbling would have an effect.
It seems rational that if scale doesn't come out after a couple o' days of tumbling, it won't.

And don't forget to pressuretest afterward!
(Less than 5 psi.)

....Cotten

[57pan]

I know this is not applicable if you're trying to save your paint, but if you are planning to repaint anyway, you could take the tanks to a powdercoater and have them run them thru their burn-off oven. This will get rid of any Kreem or varnish deposits inside the tank. It will also remove any paint and body filler from the exterior surface. Not sure that it do anything to the scale inside unless they sandblasted it.

[mbskeam]

well I did the battery charger way today and it took all of about 15 min. to get the rust out. and my paint is still good.
to get the kreem out I let a tank soak for about 4 days, it then dissolved into the lacquer thiner, and came out when I drained them.
my tank sealer should be here tomorrow, I am going with Red-kote, as it does not seam to have the same fuel issues as kreem and por15, at least not YET.......

mbskeam

[Cotten]

Here's a red sealer that lasted for many years, until last:



Sealers aren't the problem, its the P4gas.
Sturdy post-'36 HD tanks shouldn't need one anyway.

....Cotten

[mbskeam]

whats that a liver??? LOL
I thought that Bush told the gas company's that they could make gas as needed and ignore the EPA req. gas for the Midwest, as in P4....
what the hell is it made with acetone?
what was that liner?as in maker, brand.
my tanks don't leak but only trying to keep them from rusting,kinda a problem in the NW.

mbskeam

[Cotten]

Brand unknown, although I knew the past three owners who rode the warhorse to death, and the sealer never changed until suddenly last summer.
The digestive component of P4gas is a detergent or injector cleaner associated with ethanol blends. The petroleum companies are tight-lipped about what we all end up breatheing.
I dried the 'liver' and cut many small equal pieces to test in babyfood jars with a dozen or so possible culprits, including straight ethanol and several local fuels. And a piece of Buna-N o-ring was added to each as well.
Ethanol itself did not affect either the sealer or the Buna-N in the slightest.
All fuels cause the sealer and Buna-N to swell, except the ethanol-free regular!
Straight ethanol is a great motorfuel, and would help our current demands if it were applied to mass transit buses or trains. But mixing it with gasoline is stupid. It takes all economic advantage out of it (costs more to produce than it returns), screws with our hardware, and associated additives are probably a hidden health hazard that our children must deal with.

....Cotten

[PanPal]

I'm not so sure the redcoat is the same as it once was, probably the gas that is different. I have Kreme in a Honda tank, it's holding up, but I didn't like the way is seemed to bond. Almost like you could peel it if you worked at it a bit. The Por 15 seemed better and is holding up for now in the 59. Nice and hard like an epoxy with metal flake. A while back someone on Flathead power mentioned taking tanks to a place that tins copper pans. This sounds interesting if you did it before painting.

[sleeper]

Whatever modern HD is using inside their gas tanks works Great.
Even in their New manuals, it states: "if tank inside is Dirty use hot soapy water & wash it out thoroughly"..
Like to find out what they use.. Cause I froze out a dent in a '94
FLHR & it never hurt the inner tank coating..

Maybe someone here knows ?

[ridermike]

I found a rust removal product I am very impressed with. It is called EVAPO-RUST. It works as good as muratic acid (somewhat slower) but it is water based, biodegradable, and will NOT harm paint or skin. It is currently being used by the U.S. Army. It worked very well for me. I found it at http://www.theruststore.com.

[58flh]

I have used vinegar along with quarter-inch size or smaller ball-bearings! Fill a pint in the tank, put about 2shotglasses of the ballbearings in, then shake! Repeat this untill your satisfied the rust is out. This will not harm your paint-job! After all is done blow-out with compressed air, protect your paintjob real good & buy a jug of tank-creme, protect your petcock threads & fill threads! then pour that creme in & roll the tank around real good ,let it dry for 24hrs. & your good to go. stay-safe----- 58flh

[foundationapps]

HI all, I have learned tons from the riders on this site. I like to contribute as much as my brain allows. My 48 needs some bigger tanks. So I went on Ebay and found a fine deal on a set of 5 gallon black tanks that appeared and are in great condition... on the outside. Inside was a combination of Kreem (I think) in the right side with some rust working through, and plain rust in the left side tank. Fuel tank mounts were fine. Phases explained as below:

1. Stage 1 Cleaning. Both tanks filled with ripe (old) gas to look for leaks. No leaks initially found. Both tanks heavily douched with water and soap to remove any old fumes prior to placing in the wife's dryer.

2. Filled both tanks with aquarium rocks (dry, about 1/3 full). Placed one tank at a time in a sleeping bag and taped that shut. x2 army ponocho liners, 2 pillows and an old foul army sock for luck added to take up space in the dryer so the tank didn't flop around.

3. NO HEAT. Tanks one at a time in the dryer for a total of 3 hours each. Intent was to remove rust only and superficial loose crap lining these tanks.

4. Stage 2 Cleaning. Worst tank, that with Kreem and other unidentifiable sealers and rust, filled with straight Acetone. Rotated and sloshed and left to rot overnight. In the morning, dumped the acetone out through a steel screen to recover the acetone, though somewhat polluted at this point.

RESULTS AT THIS POINT. 50% still coated in Kreem, most rust removed.

5. Stage 3 Cleaning. Recovered and polluted acetone replaced back in both tanks. Sloshed around and screened and re-poured into the tanks 2 more times. A large stiff bottle type brush was used to scrub loose any Kreem residue or whatever else was in there.

RESULTS: After a 5 hour pour out and replace process, ALL rust removed that is visible to this point. Still some Kreem left behind. Left side tank that was without any coating is clean at this point. Sprayed inside with WD-40 to prevent rust while the right side tank was completed.

6. Stage 4 Cleaning. (x3 days at this point). NEW Acetone poured into Left side tank. Left this overnight. In the morning, acetone poured through screen, a glob mass about the size of a golf ball if you wadded it into a mass.

RESULTS: While some spotty Kreem remains, all rust and other residues appear gone. Considered chemically clean at this point. Next stage.

7. Stage 5. Cleaning and prep. Aquarium rocks with nuts and small bolts added to gas tank. (Right side only, left side still sitting with WD-40 inside). Taped back into sleeping bag and padded as explained above. 3 hours of cold air tumbling.

RESULTS: All rust removed, spotty on the Kreem (or whatever that crap is). Acceptable for me.

8. Full wash out and rinse. If no leaks, will NOT coat with a tank liner. I add MMO to the fuel, so rust shouldn't be a problem.

Will update.

[foundationapps]

Follow up to last post on the tank cleanup. After cleaning as much as possible and several fuel flushes, all was as clean as I was willing to complete.

Sealed the tanks and pushed in about 5 PSI of air to check for leaks, there were none. I opted OUT of adding any sealant. Adding MMO to the fuel was going to have to be good enough to prevent rust.

Reconnected the tanks, added a clean screen to the petcock, open the valve. Fuel flowed at about 50% (my guess), it clotted off. Drained the fuel, removed the petcock and found a clot of unidentifiable crap INSIDE the valve (maybe from before the tank change?).

Tank reassembled, machine has been running perfectly, after I corrected an intake manifold leak. (Thanks Richie).

FOLLOW UP ON AQUARIUM ROCKS... If you pad the tanks well enough (1 at a time), I taped mine into a sleeping bag, then packed poncho liners and pillows around the tank for additional silencer effect.... wife thought I was doing laundry so I got extra bonus points for doing laundry. I folded the poncho liners and acted like an idiot when she asked me if I actually washed the pillow too!! LOL. She never caught onto the tanks in the dryer being the center of the action.

Mission Complete.