Revotron 1.2T
83
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/cm
2
. Once the pressure
exceeds 1.4 kg/cm
2
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 :
•
Thermostat start open temperature is
88
0
±2
0
C at 0.1 mm travel.
•
Full open temperature is 102
0
C at 8mm
(Min.) travel.
•
Leakage through main valve (including
jigle pin) at room temperature and
0.2kg/cm
2
is 300cc
2
/min
