Coolant type?

[harpdevice]

Hello,
I’ve owned my 1971 Spider for a few years and never had to fill the coolant. The other day I noticed it was low. It looks like red coolant.
Does anyone know what type it might be?

[18Fiatsandcounting]

Ethylene glycol (antifreeze) is a clear, colorless liquid, but coolant manufacturers use different dyes to differentiate their products. The "old school" color was always that fluorescent green color which is caused by the dye fluorescein, which helps in leak detection if you have a UV lamp (fluorescein lights up brightly when exposed to UV). In fact, one of the tests for antifreeze poisoning is to look for the fluorescein in urine samples with a UV lamp.

But I digress. It's possible that you simply have an ethylene glycol antifreeze that happens to be red in color, but it also could be that you have an alternative antifreeze such as OAT (Organic Acid Technology) such as Dexcool.

But, a '71 spider was never designed to have anything in it except the traditional green antifreeze, and since you really don't know what your red stuff actually is, my suggestion would be to drain the whole system, flush it out, and replace with just standard ethylene glycol antifreeze. Different manufacturers (like Toyota) have specific formulations, but for a '71 Fiat, any generic antifreeze will be fine. And, again since you don't know what's in your car, don't try mixing by just topping off with green antifreeze.

-Bryan