too much water added the overflow is designed to let out water.onece the radiator reaches the required pressure,the excess water is exhausted thru the overflow
A hole.
Anything toxic can cause ground water contamination if poured on the ground.
It means you have a "BIG" leak. I would check the bottom of the radiator or the lower radiator hose.
The lower radiator hose.
thermostat, or buildup of deposits in intake and thermostat housing
Not sure what the question is getting at, but yes it does. There is no dedicated coolant radiator specifically for the intake, it shares the same coolant system and radiator as every other water-cooled system in the vehicle's engine.
No.
I don't think a blown intake gasket would cause it to overheat, Most causes of overheating are: thermostat stuck in closed position; faulty water pump; broken fan blades; loose belt; clogged radiator; radiator cap not holding pressure; blown head gasket; low or no coolant; leaking hoses.
There are several causes that will reduce the water level in your car radiator. The most common cause is evaporation. Engine overheating will also reduce the radiator water level.
Because it would cause the universe to explode
gravity pulls the water down when it is poured
No. The only times the radiator would leak is if it was damaged, defective, or corroded.