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Q&As since 1989


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Rust remover product?

I am trying to remove rust from the gas tank of my '73 Datsun. I have been sloshing mineral spirits and ball bearings around, and it is making little progress. Is there any product to help remove rust from the inside?

Charles Klimmek
- Gaylord, Minnesota, USA
2003

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A useful method would be a Molasses solution. For something the size of a petrol tank I would recommend a mixture of 25% Molasses, 25% vinegar [in bulk on eBay or Amazon], 50% Water- The water is mainly to gain the volume of solution required needed for a petrol tank (less water equals stronger solution). The molasses and vinegar are mild acids that will attack the iron oxide and not the steel. You will not find Molasses in a Supermarket. It is used as an additive for stock feed. You will find it in bulk at a Farm Produce store and is relatively inexpensive. It is a VERY thick syrup and will take some perseverance to mix in the vinegar and water. Also, mix in half a cup of bleach [adv: bleach/sodium hypochlorite in bulk on eBay or Amazon] to stop mould growing in the solution.

Mix the solution, put it in the tank along with your ball bearings and let it sit for 24 hours - give it a good shake and then let it sit in for another 24 hours - repeat this process for a week or so then drain the tank and rinse well with clean water. Use a hair dryer [on eBay or Amazon] to dry the inside of the tank completely and then use a tank sealant of your choice.

Allan Catling
- Sydney, Australia
2003

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2007

My 1968 DATSUN pickup had set for years . inside the gas tank had a healthy layer of rust.

With tank off of car. two adapters were welded up to match the mounting holes on the tank. One with a 5 foot 1" pipe and the other a 10" inch pipe. forming a "T" after welding.

I mounted the long pipe on a machine lathe to hang the gas tank out over the end. I used skate board wheels to support the weight; one set at the lathe body the other ,short end, mounted to a nearby wall also with skate board wheels.

I put in a bunch of soft volcanic rock which I got in the garden center at Osh., added sand to muffle the noise,,a little water Plugged the holes and let it turn,,,at slow speed of course.

About an hour of this noise it came out pretty clean.
Then I washed the sand out of the tank with a water hose
then removed the rocks with a shop-vac.

Carl Lowe
- Burbank, Calif, USA