Technical Tip:

Heater Core Health by Brian Robson

hood pad

Leaking heater core, Hmmm... well that's a pain to change. I've said it, and so have a lot of people I know. So it doesn’t get done.
But you really shouldn't let it go. Other than the obvious reasons, over heating, smelly, greasy windshield, mess in the car, etc... There is another reason to keep it in good condition.
If your pet, dog, cat, weasel, or whatever were to lick up a puddle of antifreeze they would die! So we stop them by whatever means necessary. Ethylene Glycol, or Propylene Glycol are POISONS!
So what do we do when we don't replace a leaking heater core? We allow hot, atomized antifreeze to be ingested into our lungs and mix directly with our blood. Some of the issues are joint pain, nausea, muscle pain, a general feeling of discomfort, fatigue, and altered mental status (unnoticeable in me). If gone untreated, kidney failure, and death may occur.
This is not just for your classic, but your daily driver as well.
Most of the health professionals I have talked to agree, and said it just had not dawned on them. And, this may be the cause of difficult to diagnose maladies they have seen.
Just a thought, but by seeing to the health of your heater core (cores), you might just be looking after your own health!