Low Coolant

• When the radiator is operating without problems, it maintains pressure and keeps the temperature consistent. But when there is a leak in the cooling system, the coolant can fall below the appropriate level.
  
  

Damaged Hose

• Rubber hoses are designed to withstand a great deal of heat carrying the coolant in and out of the radiator. If the hoses become brittle or sustain tears and rips, the radiator will have problems keeping the temperature of the engine low.
  
  

Radiator Cap

• An auto radiator will have problems keeping the necessary pressure if the radiator cap's rubber seal has tears or bubbles, which will facilitate the leaking of coolant.
  
  

Crack in Radiator

• Cracks in the radiator will cause problems, allowing coolant to leak, especially if the cracks are where the hoses are connected to the radiator.