Modern Vespa

Hi Guys,

I've read a bit, not much though, and watched a few videos on youtube about using Molasses, anybody else got some advice on how to clean up an old fuel tank without damaging it.

lots of nuts and bolts and shaking




molasses sounds like a really bad idea to me, sugar plus heat n end up with a toffee cylinder etc

If its just crappy ole fuel and sludge than simple green and good strong spray nozzle.

If its got some rust then throw some gravel or nuts and bolts or a 1'4 pound of some roofing nails in there with some simple green and shake that fucker around for a while.

If its bad do the same thing twice.

Drain cleaner will work. ONE 1/2 once PER TANK FILL WITH WATER KEEP COOL...I just don't know what you have down there to use.. I use toilet bowl cleaner or drain cleaner "acid" in my tanks.. works great..
Just let it set for two days then.. Drain 75% out and use the nut and bolt method.. "OPEN SLOWLY TO LET THE PRESSURE OUT" then flush with water... cut some two stroke oil down with gas and add right after the flush to stop flash rusting..and then your good..

For just plain rust I've had good results from molasses- the chemistry is some kind of chelation. I've used a 10% molasses and water solution, and left the parts in for a month. Here's how a 120 year bicycle chain turned out:
http://s53.photobucket.com/user/gormanao/media/Cushion%20Tire%20Safety/molasseschain.jpg.html
There are a lot of witch doctor derusting schemes. This worked for me.

yup, nuts and mineral spirits is my trick.

There is a toilet bowl cleaner called "Works" for sale for $2 at Ace hardware that you just pour in and fill the tank with water. After 10-15 minutes pour it out and the tank is bright and shiney inside. Quickly coat the inside of the tank with a gas/oil combination and away you go....

looks like it works well !!, i only put it on yoghurt or porridge cheers




still i have memories of the old trick. cup of sugar in the fuel tank of someone you hate

Better you than me. My nuts ain't going near any mineral spirit.

how much rust is inside? are we talking scale flakes or just surface?

If its just surface, then a shake with nuts, bolts, nails and 100+mls of crc for 10 minutes may do it.
But if its flaking scale, use nuts bolts nails and zinc phosphate acid. Shake for about 10 minutes, let it sit for 20 then flip it and do the other side. Rinse with water, you may need to repeat it a few times. Use a blow dryer to dry it out. Then squirt a heap of crc in there to keep it from corroding.

You can tie it to a clothes line through the bolt holes with the tap and cap plugged up and just spin it round. Works heaps easier than shaking the damn thing.

If you have rust and some scale , put some nuts, bolts, clean small gravel, etc in the tank, tape up the openings, wrap up in an old towel or blanket and run it thru a cycle in the clothes dryer - no heat of course. Just make sure your lovely lady is not home at the time, too many questions - not enough lies. Good Luck

A 10:1 water/molasses solution actually will work. It creates an acetic acid that dissolves rust. But it's a slow process. There are at least half a dozen relatively inexpensive products that remove and inhibit rust and do it much faster and more effectively using phosphoric acid solutions.

Ospho, Fast Etch, Krud Kutter's Must for Rust, even good old Naval Jelly will all deoxidize the inside of your tank and coat it in much less than a month.

I've used molasses and it hasn't taken a month. It is pretty slow thou. Toilet cleaner does work well. I shy away from putting nuts and bolts inside as sometimes a rusty tank isnt just rusty but also thin. I have rinsed with diesel fuel but premixed should do the same.

I just cleaned the tank on the rally - it was parked for 34 years. I was told to use acetone and a chain - and I used gravel instead. Medium sized gravel. I let it soak a while. Be careful the acetone will destroy paint and the knob on the fuel cap if allowed to soak. I wiped off any drips and my paint is fine.

I bought a paint shaker from Harbor Freight a few years back. I now put it to good use cleaning out tanks. A cup of 1/4 nuts and 30 minutes later the inside of the tank is spotless.

Paint shaker? Just suspend from bungees & use kidpower.

Is that legal?

That's exactly what kids were invented for.

^^^ correct

plus they earned 5 euro each for both putting in multihours of shaking.

I use the gravel method , then wrap the tank in a towel and put it in the cement mixer for a couple of hours.

hillbilly gravel ?

Of course !!!