NEXON

1.2L REVOTRON ENGINE

COMPONENTS

1. Radiator & Fan Shroud Assy

The radiator is a heat exchanger that is used to

dissipate the coolant heat. A radiator fan is used

to create forced air circulation.

Radiator consists of radiator core, inlet tank and

outlet tank.

Cores are usually made of aluminum. The core

has two sets of passages, a set of tubes and a set

of fins attached to the tubes. The tubes run from

inlet tank to outlet tank. Coolant flows through the

tubes and air flows between the fins. The

atmospheric air passing between the fins carries

away the heat, which lowers the temperature of

the coolant.

2. Auxiliary Tank

The radiator cap controls the system pressure to

1.4 kg/cm2. Once the pressure exceeds 1.4

kg/cm2 the cap lifts off the seat and the coolant is

allowed to escape into a auxiliary tank.

As the engine cools down the system pressure

falls down and vacuum is formed. The auxiliary

tank allows the water from the tank to go back into

the radiator. Thus the system does not have any

coolant loss during normal operation.

3. Thermostat

The thermostat controls the flow of coolant as

follows.

a) During a cold start, thermostat does not allow

coolant to flow to radiator since it is closed;

instead the coolant flows through thermostat

bypass outlet back to the engine. Thus short

circuiting of radiator which helps in attaining

engine working temperature in a very short

period.

b) As soon as the coolant temperature reaches

the opening temperature of the thermostat, the

thermostat valve starts opening gradually and

coolant starts flowing to the radiator. At the

same time the thermostat by-pass starts

closing gradually.

c) As the engine working temperature reaches

thermostat full open temperature, the

thermostat valve opens fully and thermostat

by-pass valve closes completely. In this

condition maximum quantity of engine coolant

flows from radiator to water pump.

Testing Parameters



Start open temp. 87 +/-2 °C at 0.1 mm travel.



Full open temp. 98 °C at 8 mm (min) travel.



Leakage through main valve at inlet pressure

of 1.0 kg/cm2, not to exceed 100 cc/minute

when water at room temperature.