How do you find an anti-freeze leak in a 1969 Chevelle Malibu?

Answer 1

If no leaks are visible on engine or radiator, check floor inside car, could be heater core, if no leak there, check engine oil dipstick & under oil fill cap for white or milky fluids, if any there will be most likely bad head gasket, cracked head, or cracked engine block.

you should pressure test the cooling to 16psi this will ake it leak faster to locate problem if you see coolant under car you can and just can.t seem to locate leak you can add ultra violet dye to your coolant drive a few miles then check car out with a blacklight most shops have this light for finding a/c leaks you are better off getting the car on a lift being the older the car the more the freeze plugs rot and leak or auto zone or pep boys sell leak detection kits (uv)