The radiator honeycomb area is clogged with sludge, sludge or scale caused by the use of non-standard radiator fluid or using water to fill the radiator for a long time. When it is clogged it will make the coolant unable to flow through the radiator and cannot circulate to the cooling system. 

The corrosion and damage of the parts around the water valve were caused by poor quality radiator.

The water pump area was damaged by corrosion causing the radiator to not be able to circulate in the system enough due to a leak. 

The cylinder surface area corrosion and leak in the parts, pitting corrosions from the use of poor-quality radiator fluid. When the engine is overheated, the refrigerant used may not have a high boiling point causing the bubble. When such bubbles occur severely it will cause these holes to leak which resulted in the coolant leaking from the system. 

The pitting corrosion at the cylinder cover area from the use of poor quality radiator. It causes the liquid to leak out of the system.

To prevent these problems to happen in the cooling system, proper and quality coolant is essential in the engine cooling system and helps prolong the life of the engine as well.