Crankshaft Pulley/Torsional Vibration Damper
| ITEM | DESCRIPTION |
|---|---|
| 1 | Bolt - Crankshaft pulley/torsional vibration damper (quantity 4) |
| 2 | Crankshaft pulley/torsional vibration damper |
| 3 | Crankshaft |
| 4 | Roll pin - Crankshaft pulley/torsional vibration damper |
The crankshaft pulley/torsional vibration damper is located at the front of the crankshaft which drives the accessory drive belt for the ancillary components. A tuned torsional vibration damper is incorporated into the crankshaft pulley which dampens vibration in the crankshaft produced by the combustion process. Each time a cylinder fires, torque is applied to the crankshaft through the pistons and connecting rods. The crankshaft deflects in reaction to the torque that creates a vibration when the torque is dissipated. The torsional damper absorbs the vibration, reducing fatigue damage to the crankshaft.
The crankshaft pulley/torsional vibration damper is located on an alignment roll pin that is pressed into the front of the crankshaft. The 4 bolts are secure the crankshaft pulley/torsional vibration damper to the crankshaft. An O-ring seal provides a seal between crankshaft pulley/torsional vibration damper hub bore and the crankshaft nose outer diameter. This prevents oil leakage during engine operation. The crankshaft pulley/torsional vibration damper hub seals to the dynamic shaft oil seal of the front cover. If the crankshaft pulley/torsional vibration damper is removed the front oil seal must be replaced.
The crankshaft pulley/torsional vibration damper has a timing mark. When the timing mark aligns to the front cover assembly timing feature, the crankshaft is 50° After Top Dead Center (ATDC) for number 1 cylinder.
The crankshaft pulley/torsional vibration damper is not a serviceable component and must not be disassembled.