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Tο κύκλωμα ψύξης του ecoboost είναι αρκετά πολύπλοκο αλλά αν λειτουργεί σωστά διευκολύνει πολύ τον κινητήρα να πιάσει γρήγορα την σωστή θερμοκρασία. Παραθέτω ένα κείμενο της αναλυτικής περιγραφής του γιά όποιον ενδιαφἐρεται.
Engine Cooling - System Operation and Component Description
System Operation
Engine coolant flows primarily from the engine to the radiator circuit and back to the coolant pump. Coolant is sent from the coolant pump through the engine block and cylinder heads. A separate circuit from the engine also feeds the heater core and turbocharger with coolant. The coolant pump, operated by engine rotation through the accessory drive belt, circulates the coolant. The coolant thermostat is a control valve actuated by coolant temperature. When the thermostat is closed, coolant flow bypasses the radiator circuit and returns to the coolant pump. When the thermostat is opened, coolant flows through the radiator circuit to transfer engine-generated heat to the outside air. The thermostat contains a bypass valve. Then the thermostat is in a closed position the bypass valve is allowed to open above 3,000 rpm to route coolant directly back to the mechanical coolant pump reducing cooling system pressure.
The degas bottle holds surplus coolant and removes air from the cooling system. It also allows for coolant expansion and system pressurization, replenishes coolant to the cooling system and serves as the location for service fill.
The thermostat monitor is a function of the PCM and is designed to verify correct thermostat operation. The monitor executes once per drive cycle and has a monitor run duration of 300-800 seconds. If a malfunction occurs, DTC P0125 or P0128 sets, and the MIL illuminates.
The engine's cooling circuit consists of an additional cylinder block thermostat. When this thermostat is in a closed position. Coolant is routed only through the exhaust side of the cylinder head, heater core, and oil cooler then returns to the mechanical coolant pump. When the cylinder block thermostat opens coolant then flows though the engine block similar to a conventional cooling system. Stagnating engine block coolant flow makes impossible for the engine components to warm up faster. The result is a significant reduction in the emissions of harmful pollutants and an improvement in fuel economy (i.e. reduced friction) during the warm-up phase.
The cooling system operates in 3 phases:
Phase 1:
When the engine is cold both the thermostat and the cylinder block thermostat are closed. The mechanical coolant pump delivers coolant only to the exhaust-side of the cylinder head. In this phase, the coolant in the coolant jackets around the cylinder and in the intake-side of the cylinder head remains stagnant. From the exhaust side of the cylinder head the coolant flows to the heater core then the oil cooler and then back to the mechanical coolant pump. In addition, part of the coolant flows from the short block through the electric water pump then through the turbocharger to the degas bottle then back to the mechanical coolant pump. If the engine speed exceeds approximately 3,000 rpm the bypass valve located in the thermostat housing opens. This allows increased pressure to escape directly to the intake side of the mechanical water pump.
Phase 2:
The cylinder block thermostat opens at a coolant temperature of 70°C (158°F) and is completely open at 85°C(185°F). The mechanical coolant pump now delivers coolant to the cooling jackets around the cylinder walls and to both sides of the cylinder head similar to a conventional system.
Phase 3:
The thermostat opens at a coolant temperature of 92°C (198°F) and is completely open at 106°C (223°F). At the same time the bypass valve closes. This ensures that the entire coolant flow, regardless of coolant pressure, is always routed via the radiator. This engine is equipped with an electric coolant pump that is secured to the cooling fan shroud. This electric water pump is normally not energized unless the engine reaches a critical temperature. This occurs if the engine has been operated at a high load then parked and the engine is turned off. This can lead to excessive build-up of heat around the engine. By circulating coolant for a certain amount of time this heat build up is reduced preventing damage. With the electrical coolant pump activated, the coolant flows through the turbocharger to the degas bottle and from there through the mechanical coolant pump in the short block to the electric coolant pump.
Engine Cooling - System Operation and Component Description
System Operation
Engine coolant flows primarily from the engine to the radiator circuit and back to the coolant pump. Coolant is sent from the coolant pump through the engine block and cylinder heads. A separate circuit from the engine also feeds the heater core and turbocharger with coolant. The coolant pump, operated by engine rotation through the accessory drive belt, circulates the coolant. The coolant thermostat is a control valve actuated by coolant temperature. When the thermostat is closed, coolant flow bypasses the radiator circuit and returns to the coolant pump. When the thermostat is opened, coolant flows through the radiator circuit to transfer engine-generated heat to the outside air. The thermostat contains a bypass valve. Then the thermostat is in a closed position the bypass valve is allowed to open above 3,000 rpm to route coolant directly back to the mechanical coolant pump reducing cooling system pressure.
The degas bottle holds surplus coolant and removes air from the cooling system. It also allows for coolant expansion and system pressurization, replenishes coolant to the cooling system and serves as the location for service fill.
The thermostat monitor is a function of the PCM and is designed to verify correct thermostat operation. The monitor executes once per drive cycle and has a monitor run duration of 300-800 seconds. If a malfunction occurs, DTC P0125 or P0128 sets, and the MIL illuminates.
The engine's cooling circuit consists of an additional cylinder block thermostat. When this thermostat is in a closed position. Coolant is routed only through the exhaust side of the cylinder head, heater core, and oil cooler then returns to the mechanical coolant pump. When the cylinder block thermostat opens coolant then flows though the engine block similar to a conventional cooling system. Stagnating engine block coolant flow makes impossible for the engine components to warm up faster. The result is a significant reduction in the emissions of harmful pollutants and an improvement in fuel economy (i.e. reduced friction) during the warm-up phase.
The cooling system operates in 3 phases:
Phase 1:
When the engine is cold both the thermostat and the cylinder block thermostat are closed. The mechanical coolant pump delivers coolant only to the exhaust-side of the cylinder head. In this phase, the coolant in the coolant jackets around the cylinder and in the intake-side of the cylinder head remains stagnant. From the exhaust side of the cylinder head the coolant flows to the heater core then the oil cooler and then back to the mechanical coolant pump. In addition, part of the coolant flows from the short block through the electric water pump then through the turbocharger to the degas bottle then back to the mechanical coolant pump. If the engine speed exceeds approximately 3,000 rpm the bypass valve located in the thermostat housing opens. This allows increased pressure to escape directly to the intake side of the mechanical water pump.
Phase 2:
The cylinder block thermostat opens at a coolant temperature of 70°C (158°F) and is completely open at 85°C(185°F). The mechanical coolant pump now delivers coolant to the cooling jackets around the cylinder walls and to both sides of the cylinder head similar to a conventional system.
Phase 3:
The thermostat opens at a coolant temperature of 92°C (198°F) and is completely open at 106°C (223°F). At the same time the bypass valve closes. This ensures that the entire coolant flow, regardless of coolant pressure, is always routed via the radiator. This engine is equipped with an electric coolant pump that is secured to the cooling fan shroud. This electric water pump is normally not energized unless the engine reaches a critical temperature. This occurs if the engine has been operated at a high load then parked and the engine is turned off. This can lead to excessive build-up of heat around the engine. By circulating coolant for a certain amount of time this heat build up is reduced preventing damage. With the electrical coolant pump activated, the coolant flows through the turbocharger to the degas bottle and from there through the mechanical coolant pump in the short block to the electric coolant pump.