Soak the whole thing in lemon juice for a while.

Then rinse with water and either let dry or dry with compressed air.

cyclone3d wrote:

Soak the whole thing in lemon juice for a while.

Then rinse with water and either let dry or dry with compressed air.

Better to do it this way:
https://www.youtube.com/watch?v=oC-A2qsbV_U

Soak in vinegar/salt/water solution, then neutralize in a water/baking soda solution.

Remove the fan first, obviously.

thanks. the cooler is so big that i will have to use water+vinegar+salt

because i need to put it in a bowl

Yeah.. that works as well.

I prefer the ketchup method.

I find citric acid more effective than vinegar for removing rust/tarnish. It's also cheaper and doesn't smell. You just need to prepare saturated solution.