Reply to "Cooling issue addendum"

In a "normal" front engine car the engine sits at an angle, with the front of the engine slightly higher than the rear of the engine, air in the block or heads migrates forward, passes out via the thermostat and collects in the radiator.

I drove 2 different 351C powered Mach I Mustangs as my daily drivers for a large part of my adult life (1970s through 1990s), those cars were always lowered a bit in the front, which negated the angle of the engine due to the drivetrain. My cars never had a problem with air collecting in the engine, never had any kind of over-heating problem, never had any problem purging air from the engine after I had flushed the cooling system & replaced the coolant.

Yes, in the Pantera the engine sits flat, but as you drive the car you go up hills and up driveways, the front of the car is higher than the rear, the air in the block has plenty of opportunity to migrate to the front of the engine block and pass out of the block via the thermostat in the normal manner.

With the Pantera, the best thing you can do to help servicing the radiator is to put a drain-cock valve in one of the radiator tanks to replace the factory vent which doesn't work. As you fill the system you simply bleed air from the radiator with that drain-cock. To get the air out of the engine, elevate the front of the car for a minute or two after the engine has reached operating temp and the thermostat has opened up. Any air in the block or heads will migrate to the front of the engine and pass out via the thermostat as it does in any 351C equipped car. The air that passes out of the engine will collect in the "system tank" or find its way to the radiator.