Contents: General information ⇩ Engine cooling system ⇩
| Item name | Spare part catalog number | Description |
| 1 | - | Heater hoses, inlet and outlet |
| 2 | - | Rear Heater Connections |
| 3 | - | The hose connecting the radiator to the expansion tank |
| 4 | - | Throttle body |
| 5 | - | EGR valve |
| 6 | - | Air bleed screw |
| 7 | - | Hose connecting the exhaust pipe to the cylinder block |
| 8 | - | Exhaust pipe assembly |
| 9 | - | Expansion tank |
| 10 | - | The hose connecting the heater to the thermostat |
| 11 | - | Cylinder block |
| 12 | - | Water pump |
| 13 | - | The hose connecting the radiator to the thermostat |
| 14 | - | Oil cooler |
| 15 | - | Cooling fan |
| 16 | - | Lower casing |
| 17 | - | Transmission fluid lines |
| 18 | - | Radiator |
| 19 | - | Upper casing |
| 20 | - | The hose connecting the outlet pipe to the radiator |
General information
A bypass cooling system is used, providing circulation of coolant through the engine and heater circuit with the main thermostat valve closed. The main purpose of the engine cooling system is to maintain the optimum engine temperature when environmental conditions and engine operating mode change. Other functions of the cooling system include heating the car interior and cooling the working fluid of the gearbox and engine oil.
The cooling system includes the following components:
- Radiator
- Car interior heater core
- Coolant pump
- Thermostat
- Expansion tank
- Fan with electro-viscous coupling
- Connecting hoses and pipelines
Engine cooling system
The coolant is circulated through the system by a centrifugal pump mounted at the front of the engine and driven by an additional poly V-belt. The pump pumps the coolant through the cylinder block and cylinder heads through a chamber located in the cylinder block camber. After passing through the engine, the working fluid returns to the thermostat housing. The fluid then flows through the upper hose to the interior heater tube. The heater tubes pass through the engine compartment bulkhead and return to the engine in the thermostat area.
The engine has a conventional thermostat, which is positioned so that the temperature of its sensing element is determined by the flow of coolant from both the radiator and the bypass channel. As a result, the opening temperature of the thermostat can vary depending on environmental conditions. The thermostat housing contains a spring-loaded valve that restricts the flow of fluid through the bypass channel. This means that the engine can temporarily run without fluid flowing through the bypass channel, which in turn improves the operation of the interior heater.
The horizontal flow radiator has an aluminum alloy core and a drain cock on the lower right side of the rear. The lower radiator mounts are on the ends of the radiator tanks. The mounts have rubber grommets that are mounted on the top of the vehicle body rails. The top of the radiator is secured with pins that are threaded through rubber grommets mounted on the front end carrier (FEC) above the radiator. The radiator also has two connections for the transmission oil pipes built into it.
The upper and lower hoses are attached to the inlet and outlet ports of the thermostat housing.
The expansion tank is installed in front of the left support cup of the suspension in the engine compartment. The expansion tank receives excess amount of working fluid from the cooling system when it expands due to heating and, conversely, when the engine cools down, compensates for its amount when the volume decreases. Air accumulated in the cooling liquid is also discharged through this tank.
The transmission fluid cooler is installed on the side of the cold radiator tank. It is located in the middle of the left radiator tank.
The engine oil cooler (EOC) receives coolant from the lower hose. Coolant is diverted from the line between the radiator and thermostat and sent to the oil cooler, then returned to the lower hose.
To provide additional air to the radiator core, especially when the vehicle is stationary, a viscous coupling fan driven by the engine is used. This unit operates like a conventional viscous coupling fan, but with an electronic drive for viscous coupling engagement. The electronic engine control unit (ECM) controls the fan speed by regulating the degree of viscous coupling engagement. The viscous coupling is engaged by the control unit based on the coolant temperature, ambient temperature, gearbox oil temperature, and air conditioning system pressure. The fan used has a left-hand rotation.
The speed of the viscous fan is optimally regulated by the ECM to suit all operating conditions.
NOTE: If the electrical connectors are disconnected from the viscous fan, the fan will run at "idle speed" which may cause the engine to overheat. In this case, the ECM will store a corresponding DTC.
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