Does copper oxide "spread" in a closed loop
 

So I've got some copper blocks in my loop, and a 1987 ford econoline van heatercore for a radiator. that core has some greenish copper "petina" on the inside that I can't seem to get rid of... it also doesn't seem to come out in the coolant particularly... maybe a little clouding. Will it just "stay" there or will it spread to the coolant if I'm running distilled water and just a little dye?

Thanks you geniuses!

Re: Does copper oxide "spread" in a closed loop
 

Some of it should come off, bit by bit (ever so slowly), everytime that you flush the system.

What should be going on (someone correct me if I'm off) is that this residue (copper oxide) will get dissolved into the water, until it's saturated. Not hard to do when you start with distilled water.

You could try flushing out the rad with a warm vinegar solution to accelerate the process; just set it up in a loop with a pump and airtrap only, and let it run overnight. Not sure how you'd keep it warm that long though.

Report results. ;)