Description And Operation: Engine: Description: Crankshaft
| ITEM | DESCRIPTION |
|---|---|
| 1 | Thrust washers (2 off) |
| 2 | Upper main bearings (5 off) |
| 3 | Crankshaft |
| 4 | Mass damper location |
| 5 | Alignment roll pin - Mass damper |
| 6 | Lower main bearing - No. 1-4 (4 off) |
| 7 | Lower main bearing - No 5 |
| 8 | Dynamic balancer drive gear |
| 9 | Timing chain drive sprocket |
| 10 | Alignment dowel - Drive plate |
The crankshaft is manufactured from forged carbon steel C38 MOD with induction hardened main and big end bearing journals. The fillets of the main and big end journals are fillet rolled to improve the strength of the crankshaft.
A five counterweight design has been used to reduce bearing loads as well as to give class leading vibration levels.
An oil groove in the upper half of each main bearing transfers pressurized engine oil into the crankshaft:
- For lubrication of the main bearings
- For lubrication of the connecting rod bearings.
There are two different lower main bearing designs. First four lower main bearings do not have oil grooves and holes. The fifth (rear) lower main bearing has partial grooves at each end to improve the oil supply to the fourth connecting rod bearing.
The crankshaft assembly comprises the bare crank and a dynamic balancer system drive gear. This gives direct drive at a ratio of 2:1 of the two counter rotating dynamic balancers.
Two individual thrust washers are located on either side of the central main bearing journal panel of the cylinder block to control crankshaft end float.