Description And Operation
The turbochargers boost pressure is controlled using vacuum operated mechanical actuators and wastegates which are plumbed to the vacuum reservoir. The wastegates are opened and closed using a vacuum solenoid valve. When energized, provides vacuum to the actuator to close the wastegate, which is normally open. The wastegate retains its open position due to a spring internal to the actuator.
- 1 - Vacuum reservoir with connection pipe.
- 2 - Left bank solenoid valve waste-gate.
- 3 - Solenoid valve connection pipe - waste-gate actuator.
- 4 - T joint.
- 5 - Vacuum reservoir connection pipe - right bank solenoid valve.
At the minimum motor in the connection pipe (3) a depression is sent by the solenoid valve to keep the waste-gate door closed (normally it is open). The depression value that lets the actuator to completely close the waste-gate door is around 700 mbar (absolute pressure).
The connection pipe (1) to the vacuum reservoir is sent via a T joint (4) in two connecting pipes, one of which is connected to the left bank solenoid valve (2) and the other to the right bank solenoid valve (5).
The solenoid valve receives the vacuum from the pipe coming from the T joint, to then send it to the left waste-gate actuator through the pipe (3).
The same connection logic is repeated for the right bank solenoid valve and waste-gate actuator (as shown in illustration ).
- 2 - Right bank solenoid valve waste-gate.
- 3 - Solenoid valve - wastegate actuator connection pipe.
- 4 - T joint.
- 5 - Vacuum reservoir connection pipe - right bank solenoid valve.