Description And Operation
The mechanical parts of the engine are lubricated by a complex system of internal passages to the block, the cylinder heads, and the cylinder head covers. The lubrication system also owes its complexity to the hydraulically actuated systems such as phase variators and cylinder deactivation. The lubrication system consists of the following components:
- 1 - Variable displacement oil pump.
- 2 - Oil exit regulatory solenoid valve.
- 3 - Oil timing chamber for cylinder heads and block passages.
- 4 - Oil filter.
- 5 - Oil pressure sensor.
- 1 - Oil pump pick-up.
- 2 - Pump body.
- 3 - Pump drive gear.
- 4 - Pump supply.
- 5 - Mechanical regulation of the oil flow towards the sump drain.
- 6 - Oil drain towards the sump intercepted by the oil drain solenoid valve regulator.
- 7 - Oil intake (this entry's function is to allow for regulator 5 to function properly).
- 8 - Oil supply pressure regulation.
- 1 - Solenoid valve to regulate the oil pump drain.
- 2 - Mechanical valve to regulate oil drain.
- 3 - Restriction to reduce pressure.
- 4 - Pump body.
- 5 - Pump floating stator.
- 6 - Supply pressure regulator.
To vary the oil pump displacement, the ECM1 Master regulates the oil drain towards the sump.
The pump changes its displacement when the ECM1 Master controls the solenoid valve that regulates the oil drain. The solenoid circuit is controlled On or Off through grounding of the solenoid circuit. With the solenoid Off, the pump is in maximum displacement.
When the solenoid valve is Off, the pump's floating stator is completely moved to the left because the pressure in the oil drain chamber (to the left of the stator) is about equal to the sent oil supply. When the solenoid valve is On, the oil in the chamber to the right of the stator goes into drain and consequently the oil pressure there decreases significantly, determining the stator's movement towards the right. In this situation, the pump assumes the lowest displacement.
In conditions of minimum displacement, the pump transfers the oil supply enough volume so it assumes a low pressure value (LP). In conditions if maximum displacement, the pump transfers the oil supply enough volume so it assumes a high pressure value (HP).
The oil filter is the cartridge type and located on the block between the two banks (transmission/timing side).
The oil pressure sensor is positioned on the filter support. There is a rubber gasket on the filter support interface and the block.
The outgoing oil from the pump flows through the block along the passage to the heat exchanger inlet placed between the two banks. Once cooled, the oil goes out of the exchanger to head towards the oil filter inlet where it will be filtered.
There is a single directional mechanical valve in the block where the oil pump supply is inserted that allows the oil to pass only from the pump to the block and not the other way.
Once filtered, the oil comes out of the filter and runs along the main passage to reach a timing chamber where the oil is misted towards the cylinder heads and in the block lubrication's main passage.
- 1 - Main lubrication passage in the block.
- 2 - Oil feed channel for the piston crown cooling nozzles (right bank).
- 3 - Oil feed channel for the piston crown cooling nozzles (left bank).
The passages carrying oil to the camshaft bank bearings are connected to the main block lubrication.
Oil from the cylinder head is routed through passages to the side drain nozzles used to aim the stream under the piston crowns to ensure their cooling.
There is also another series of nozzles that cool the piston on the intake side.
The two turbochargers get lubrication oil for the interior bearing from the pipes connected to the engine block.
The left bank turbocharger uses the oil flow coming from an internal passage that is connected to the passage that carries the oil towards the cylinder heads. The oil is carried to the turbocharger body inlet through the pipe (1). After lubricating the shaft impeller bearings, the oil flows back from the turbocharger to fall back into the oil sump through the pipe (2).
The oil in the turbocharger inlet is regulated by a solenoid valve placed on the cylinder heads. The reason there is a solenoid valve to control the oil flow is because there is a cylinder deactivation system in the right bank.
When the solenoid valve allows its passage, the oil arrives through the pipe (2) to lubricate the shaft bearings that connect the two turbocharger impellers.
The oil leaves the turbocharger and drains off via pipe 3.