ALTROZ SERVICE MANUAL

1.5L REVOTORQ ENGINE 74 COMPONENTS A. Radiator 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 an 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. B. No Loss Tank As the engine cools down the system pressure falls down and vacuum is formed. The vacuum valve in radiator cap opens and allows the water from the No Loss tank to return into the radiator. Thus the system does not have any coolant loss during normal operation. C. Thermostat The thermostat controls the flow of coolant as follows. 1. During a cold start, thermostat does not allow coolant to flow to radiator since it is closed; instead the coolant flows through bypass outlet back to the engine .Thus short circuiting of radiator which helps in attaining engine working temperature in a very short period. 2. 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. 3. As the engine working temperature reaches thermostat full open temperature, the thermostat valve opens fully. In this condition maximum quantity of engine coolant flows from radiator to water pump. Testing Parameters  Thermostat start open temperature is 86º to 90ºC at 0.1mm travel.  Full open travel of 8 mm (Min.) at temperature is 100º C  Leakage through main valve at room temperature and 0.3 kg/cm 2 is 1500cc/min MAX.