i have a 70 ford custom when i drive it the windshield get cloudy at the bottom does that mean its separation

 

If it's pasty white around the edges, it likely is just old.

If it's fogging up(damp) on the inside, could be heater leaking antifreeze.

 

From my own experience, this could be caused from a few things. All cause fogginess to a different degree. As Shiftoholic stated, this could be from a leak in the cooling system, possibly the heater core. To check this, you can warm the vehicle up. After it's at running temperature, keep your eyes on the windshield for a few min. Then try turning on the defrost for a short while and be smelling for anti-freeze or humidity. You also might be right about the seal being bad. I would hook up a spray nozzle to the end of a garden hose and force the water pressure into the old seal for about 5-10 min. Check inside for any drips or standing water. This sounds like a very minor ordeal and believe you should have it resolved in a short period of time.
Please let me know if I was any help. I am new to this site and want to start this off right. Good luck.
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