Topic: Molasses Rust Removal

[MikeSimon]

I am using a 6:1 mix of Water/Molasses to de-rust a fuel tank inside. Only thing I cannot find is a definite answer on how long to leave the mix sitting inside. Anybody?

[flybox1]

A week....maybe.  That's a slow process.

Slow.

....like molasses.


Vinegar is faster.  So is prep-n-etch.
Both are safe for paint.

[TwoTired]

It's still an acid.  Eats rust and metal with indiscretion.  Thins metal encourages pin holes.

[PlungerWaffle]

I use vinegar and pea gravel. Cleans it up in a matter of minutes. Leaves your arms sore though, and there might be a risk for holes but successful the few times ive tried it.

[BomberMann650]

This stuff will clean the molasses and the rust out.

[MikeSimon]

I do have a procedure for cleaning the tank after the molasses treatment. What I do not have is an idea about how long I have to leave the mix in. It seems a week may be the answer. I heard it depends on the mix ratio.

[Deltarider]

I'd start with the easiest (and least harmful): pour in a litre of diesel and move it around and see where that gets you.

[MikeSimon]

So, has anybody used molasses and water? How long?

[Bodi]

Look for "Tubalcain" on youtube. He has a series on rust removal including molasses. Might have some clues on how long. I think it was the poorest of all the things he tested.

[jonda500]

It not only depends on the mix ratio but also on the ambient air temperature. I leave the "part" soaking in molasses for several days or more, good to clean up thoroughly halfway through and put back in to finish. The bubbles/froth floating on top tell you it's working, when the rust is all eaten the froth stops. I did not notice any not rusted metal get eaten at all?
John
Who can guess what two items I am derusting below? 

[eigenvector]

Seat pan and something else.

[jonda500]

yep, and battery cage
John