Automotive parts related business

Radiator cap

Radiator cap

Radiator cap is an important part for cars.

At first glance, it is a small part, but it plays an important role.
Although it looks like a lid, it is not just a lid. Three valves on the back of the cap play three roles: they keep the pressure of the radiator normal and prevent the coolant from boiling and vaporizing when the water temperature rises.

cap description
Pressurized valve
As the temperature of the cooling water rises, the pressure in the radiator goes up and the boiling point of the coolant also rises. If the boiling point increases, it exerts a cooling effect even at 100 degrees or more. Therefore, if it exceeds the pressure set there, the pressurizing valve will be opened to release extra cooling water into the reservoir tank.
Negative pressure valve
The pressure in the radiator also drops by releasing the cooling water to the reservoir tank. When the pressure in the radiator is negative, the radiator fails, so when the radiator is broken, the negative pressure valve is opened, and the pressure is adjusted by returning the cooling water from the reservoir tank.
Closed valve
A closed valve that seals so that cooling water does not leak from the radiator.
Periodic inspection and replacement

Radiator cap is an important part that keeps the pressure of the cooling cycle properly.
Due to the dirt, rusting, deposits, seal deterioration, deformation, damage, etc. of the radiator cap, the operation is worse and it may cause radiator leakage and overheat.
In order to keep the inside of the radiator normal, the rubber packing of the cap should be visually checked for deterioration or deformation, and if it is difficult to understand, it should be inspected or replaced using a tester to keep proper pressure.

check image


Radiator cap specification and design can be changed in accordance with various uses.
If you are interested in OEM, please feel free to contact us.

  • S905
    49kpa | 0.5kgf/㎠
  • S109
    88kpa | 0.9kgf/㎠
  • S209
    88kpa | 0.9kgf/㎠
  • S909
    88kpa | 0.9kgf/㎠
  • S211
    108kpa | 1.1kgf/㎠
  • S311
    108kpa | 1.1kgf/㎠
  • DTEC_B05
    49kpa | 0.5kgf/㎠
  • DTEC_C09
    88kpa | 0.9kgf/㎠
  • DTEC_D09
    88kpa | 0.9kgf/㎠
  • DTEC_B09
    88kpa | 0.9kgf/㎠
  • DTEC_D11
    108kpa | 1.1kgf/㎠
  • DTEC_C11
    108kpa | 1.1kgf/㎠


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