Cracked Radiator/Coolant Question

[Blackrosepet]

Timeline:
- at gas station, noticed i was leaking antifreeze, not drops but like a river flowing from under the car.
-nursed it to my mechanic, a short drive away. under the hood showed signs of spatter, the air box was covered with coolant. diagnosis: cracked radiator
-drove it home and parked it for a couple days.

Got tired of it sitting there and started experimenting. I added some coolant and took it for a drive, enough to get it hot and the thermostat open. It gets a tad bit hotter than usual, but not "hot". Maybe to the O in 'normal' on the gauge. Also, nothing is leaking, no drips, no spatter, it's just totally dry. So, what's up with my radiator? How could it leak significantly one day but then not leak at all the next? This car has been known to repair itself. Don't ask.

 

[Chythar]

The radiator is definitely cracked. Mustangs are known for cracking radiators on the passenger side, it's a flex point for the chassis. However, it may not leak because the sytem can no longer pressurize. Remember, coolant (water) expands under pressure. The crack is likely allowing steam to vent, thus not letting the coolant system pressurize and work properly. Or it's dribbling a bit of coolant and it's evaporating before it hits the ground. This is a common problem on our cars, and the solution is simply a new radiator.

 

[toyman]

Take the guess work out. Have the system pressure tested. The leak source will be obvious.