Engine - INGENIUM I6 3.0L Petrol (G2299994): Description: Camshafts
| Item | Description |
|---|---|
| 1 | Ball bearing - Exhaust camshaft |
| 2 | Exhaust camshaft lobe (quantity 12) |
| 3 | Exhaust camshaft |
| 4 | Needle roller bearing - Exhaust camshaft (quantity 6) |
| 5 | Reluctor ring - Camshaft Position (CMP) sensor |
| 6 | Needle roller bearing - Intake camshaft (quantity 6) |
| 7 | Intake camshaft lobe (quantity 6) |
| 8 | Intake camshaft |
| 9 | High Pressure (HP) fuel pump lobe |
| 10 | Ball bearing - Intake camshaft |
The engine is equipped with a Double Overhead Camshaft (DOHC) configuration, which uses 2 camshafts:
- There is 1 intake camshaft
- There is 1 exhaust camshaft.
The lobes on the exhaust camshaft control the opening and closing of the exhaust valves via the roller finger cam followers. There is a lobe that drives the High Pressure (HP) fuel pump.
The lobes on the intake camshaft control the opening and closing of the intake valves via the 2 Continuous Variable Valve Lift (CVVL) assemblies.
The camshafts run on needle roller bearings to reduce friction and minimize the breakaway torque on engine startup. The needle roller bearings are housed in the camshaft carrier and the camshaft caps are marked with 'I' and 'E' to denote inlet and exhaust. The camshaft caps are also numbered to help assembly in the correct position in the camshaft carrier. For example 'I4' or 'E1'.
The camshafts are of a hollow steel tube construction, with pressed on forged lobes and needle roller bearings. The hollow tube design provides reduced weight for increased engine performance. Each camshaft has a pressed-on drive adapter, which locates a drive sprocket and the Variable Camshaft Timing (VCT) actuator. Each drive adapter is equipped with a timing pin. The timing pin locates the drive sprocket and the VCT actuator on the camshaft relative to the lobe positions. Each camshaft has a pressed on reluctor ring for use with the Camshaft Position (CMP) sensors.
The VCT actuator contains a sprocket, which drives the camshaft via a timing chain, driven from the crankshaft. The VCT actuator adjusts the timing of both camshafts, increasing engine efficiency and performance, as required. The reluctor wheels are pressed on to the opposite end of the exhaust camshafts, which are monitored by the CMP sensors. The CMP sensor signals are used by the Powertrain Control Module (PCM) and enable the PCM to determine the position of the camshafts. The camshafts can then be phased by the VCT actuators to provide increased performance and efficiency.