Timing, Pump and Crankshaft Gears for Cummins

Cummins engines have many gears. These engines didn't have timing belts or chains, they had gears. A gear on the crank, camshaft diesel pump And hydraulic pump. The gears are what sets the timing for the engine. In general, they are all just press-fit, but some also have keys. Normally they all last a long time, but sometimes they do go bad.

Here are the gears: