Cooling System: Operation
| 1 - WATER PUMP |
| 6 - EGR COOLER |
| 2 - ENGINE OIL COOLER |
| 7 - HEATER CORE |
| 3 - ENGINE |
| 8 - COOLING CIRCUIT BREATHER PIPE |
| 4 - RADIATOR |
| 9 - PRESSURIZED COOLANT BOTTLE |
| 5 - THERMOSTAT |
| 10 - DEGAS HOSE |
The engine cooling systems primary purpose is to maintain engine temperature in a range that will provide satisfactory engine performance and emission levels under all expected driving conditions. It also provides hot coolant for heater performance. It does this by transferring heat from engine metal to coolant, moving this heated coolant to the radiator, and then transferring this heat to the ambient air.
- When engine is cold: thermostat is closed, cooling system has no flow through the radiator. The coolant bypass flows through the engine only.
- When engine is warm: thermostat is open, cooling system has bypass flow and coolant flow through radiator.
| 1 - RADIATOR |
| 6 - REAR HEATER CORE |
| 2 - RIGHT CYLINDER HEAD |
| 7 - FRONT HEATER CORE |
| 3 - THERMOSTAT |
| 8 - OIL COOLER |
| 4 - WATER CROSSOVER |
| 9 - WATER PUMP |
| 5 - LEFT CYLINDER HEAD |
| 10 - CYLINDER BLOCK |
The engine cooling systems primary purpose is to maintain engine temperature in a range that will provide satisfactory engine performance and emission levels under all expected driving conditions. It also provides hot coolant for heater performance. It does this by transferring heat from engine metal to coolant, moving this heated coolant to the radiator, and then transferring this heat to the ambient air.
- When engine is cold: thermostat is closed, cooling system has no flow through the radiator. The coolant bypass flows through the engine only.
- When engine is warm: thermostat is open, cooling system has bypass flow and coolant flow through radiator.