Green antifreeze or coolant as some call it.

Bills65Dart said
I totally understand what you are saying. The reason this came up is that hopefully in not too long time I will try to connect the heater core and then need to add some fluid. Now, the car has been going in the Los Angeles are without air condition, and I was thinking maybe that was the reason it was disconnected. But it might be a leaking heater core too. And if the leak is very small, I might end up trying something like bars leak or whatever to seal it. Or get the heater core fixed. And then we'll, the system needs to be flushed and new coolant put it. However, a good flush could be a smart thing in any case. When it comes to mixing coolant types I have a "reputation" for just adding up water if I don't have the same brand that is on the car.
Bill

For 'pour in' repairs use the ginger root based stuff. GM used it for their fix when they had a problems. Actually looks like pellets.
Nothing wrong with using water for cooling especially if you suspect a leak. In your climate, you might be able to get by with water plus a corrossion inhibiter and water pump lubricant additive.
Of course if you forget that there's only water in there and it freezes....not that I ever did that.:rolleyes:
It was a very cold drive home. Amazing nothing broke. Prob wasn't frozen throughout. Chevy straight 6 250 with worn bearings. Figured it might be finally done for, but it wasn't.

The block water jacket is where I've found a lot of accumulation of scale, rust, deposits. Heck some of it might be sand left over from the casting process. Anyway I replace coolant more frequently than I used to. OK. Truth be I never used to replace it as regular maintance - on an old car you wan t to keep - that's a mistake.

toolmanmike said
Walmart "Super Tech" store brand is Ethylene Glycol. https://www.walmart.com/ip/Super-Tech-50-50-Antifreeze-Coolant-Pre-Mix/16928010

All coolants are either ethylene glycol or propylene glycol. Without an addititve package both are pretty aggressive in eating away at some metals, especially when mixed with water.
Ethylene glycol is still the most common base. It's also the one that if ingested in even small amounts will kill a dog (or any other small animal). Propylene glycol is hands down better base in terms of toxicity. This is one of hte reasons I rarely would bring my dog to the garage and yard I rent, and always be real alert if start sniffing in the curbs or street gutters.