Green "kidney stones" in radiator and t'stat?

Hey guys,

Would anyone know what is causing my radiator tubes and t'stat housing to get gunked up with small pale-green mineral deposits?

I didn't find answers online. From the looks of it, the deposits are a copper-mineral accretion, could be from minerals in our water and copper from the radiator? I tend to use distilled water and Glycol, but I know I've also used tap water on occasion.
Time flies so it doesn't seem long ago, but that radiator was last recored around 2002, so it's been in service some 19 years, same thing with the t'stat and housing.
.. and I'm embarrassed how rusty and gross my engine looks in the photos.. It'll be garaged and worked on over the winter.

Is this a familiar problem for anyone, or is it just a normal service-life issue and time to have it all flushed out and restored, new hoses, etc?

Thanks,
- Art

It could probably dry copper oxide or chloride.

Almost looks like d-Con pellets. Mice like to hide those inside dormant engines.

Maybe the result of living in hard water area and using tap v/s distilled water when doing the coolant flushes?

How many times has it been flushed in the last 19 years? I suspect it hasn't been.

Antifreeze will eat aluminum over time, the results look a lot like what you have. Notice the deuteration of the T stat housing? A flush and refill about every 7-8 years seems to help in that situation. Gene

Thanks guys, that is some helpful info.
The t-stat neck was surprising crusty - I scraped a lot of mineral deposit salt-like crystals off it all the way around the neck, even filed, rough sanded and scotchbrighted it clean, then gooped it with non-hardening gasket seal and reinstalled the hose which was in good shape.

Yeah, the last time I flushed anything, it was a backflush like 4 years ago because the heater core wasn't giving off any heat - plugged up with crud. The backflush got the heater core crud out immediately, and the heat worked fine after that. I am sure I just used plain old garden hose water, and our water here is hard enough to warrant a water softener for the house.. so minerals.

I don't recall having done anything else with the radiator or block.
So, I'll go ahead and start fresh - flush it out with garden hose water, then see what I can eject with compressed air, and refill it with properly mixed Prestone and distilled water.

I have an aluminum engine car and the manual says to drain, flush and replace coolant every 5 years. I'll adopt that interval.
Cheers,
- Art

Calcium and mineral deposits

Maybe green from brass radiator and heater core. Brass is a combo of Copper and Zinc. And they tend to oxidize green.

There used to be a green pellet substance that was made for radiator plugging, came in a bottle and you poured it in when hot. Maybe some of those didn't dissolve all the way...

Small debris in the pale they used to add more water?????

Think of all we have done over the past 40 years just to get a mopar home safe.

Or even old casting material from the block.

I still find lil collected areas I chip out even in the oil exposed areas inside some blocks after the hot tank.