unbelievable, tank cleaned with vinegar

[DOINTHETON]

had three year old gas and rust in the gas tank of my old bmw. wanted to try to preserve the original paint, so i cringed at the thought of using any acid or corrosive for fear it would have the expected results if spilled. i did flush it out twice with acetone, power washing it afterwards each time. i then read that white vinegar dissolves rust. hmmm, why not. well i put two gallons in the tank and let it sit for a few days, actually kind of forgot about it, working on other aspects of this bikes ressurection. i looked in the tank this morning and it appeared the rust got worse, almost thicker. ****, better drain it and power wash one more time. so i took said tank up to the car wash, did my thing and took it home. i set the tank up on its end, and positioned my power fan to blow air through the cap and out the petcock holes. just for kicks i got my flashlight, looked in the tank and almost fell over. rust gone!,the old varnished gas in the tank, gone!
boys i'll try to get a pic posted but i'm still in a state of shock.......

[Bill Burke]

Now you might want to etch the bare metal with phosphoric acid to give it some protection from flash rusting. Vinegar is acidic, but so far as I know has no rust-prevention characteristics.

If you enjoy reading: http://bmwmotorcycletech.info/fuelmiscl.htm

[RandyB]

If you enjoy reading: http://bmwmotorcycletech.info/fuelmiscl.htm

Safety note: Wear sunglasses when reading Snowbum's site.

I used the electrolytic method and it sucked the rust right out. Vinegar certainly is easier. I also dropped the tank off at the local radiator shop to be boiled and lined. Do NOT do this unless you are planning to repaint.

[535is]

had three year old gas and rust in the gas tank of my old bmw. wanted to try to preserve the original paint, so i cringed at the thought of using any acid or corrosive for fear it would have the expected results if spilled. i did flush it out twice with acetone, power washing it afterwards each time.

i'm still in a state of shock.......

No more shocked than me. You were worried about hurting the paint and you used acetone!? :jawdrop

There are very few more effective solvents for paint than acetone. Only a concentrated acid would be more destructive. You might want to do a little better research before your next chemical treatments of anything.

[DOINTHETON]

No more shocked than me. You were worried about hurting the paint and you used acetone!? :jawdrop

There are very few more effective solvents for paint than acetone. Only a concentrated acid would be more destructive. You might want to do a little better research before your next chemical treatments of anything.


well looks like we differ in treatments.

[535is]

well looks like we differ in treatments.
One of us spent over a decade working in chemical research labs using acetone on an almost daily basis. I am very familiar with what it can do to just about any substance you can name.

[GlobalRider]

I cringed at the thought of using any acid or corrosive for fear it would have the expected results if spilled. I did flush it out twice with acetone.

The acetone would have done more damage if you spilled it on the paint.

I've used heavy duty radiator flush and hot water (speeds up the reaction) in an old rusty gas tank. It looked like new after two applications.

Gas line antifreeze was used to absorb the water after I flushed/rinsed the tank with water after the acid treatment.

Now I just put a liter of oil in an empty gas tank and slosh it around if it is going to be stored.

[535is]

The acetone would have done more damage if you spilled it on the paint.

I've used heavy duty radiator flush and hot water (speeds up the reaction) in an old rusty gas tank. It looked like new after two applications.
As well as the vinegar, a good choice.
Gas line antifreeze was used to absorb the water after I flushed/rinsed the tank with water after the acid treatment.
I'd read that container carefully to avoid any low level paint-eating nasties. Sometimes, the cheapest stuff is the best way to go. Alcohols mix with water quite nicely. That's most of what fuel line antifreeze is. But ethanol and isopropanol sell for about $1 a pint in any drugstore. Both evaporate quickly or, if mixed with fuel, go right through the carbs and burn. They have almost no effect on paint, so they would be among my first choices to dry a tank of the rinse water after using an acid wash.
Now I just put a liter of oil in an empty gas tank and slosh it around if it is going to be stored.
That could work ... :thumb

[DOINTHETON]

well, thanks for the info. the tank rests now with five gallons of vinegar in it as a second application. i'll use the tips on drying out after the next flush.
thanks again.

[GlobalRider]

Alcohols mix with water quite nicely. That's most of what fuel line antifreeze is. But ethanol and isopropanol sell for about $1 a pint in any drugstore.

Which is what I use. I have a gallon jug on hand at all times.

[crazydrummerdude]

I'd heard the vinegar treatment thing on advrider before. It's good to see a pic of the proof.

[DOINTHETON]

kind of a crappy pic. if you look at the filler neck, it gives you an idea of what the inside of the tank looked like.