617 diesel: steady rhythmic tick tick tick tick sound from engine

[HuskyMan]

1984 300DT 5 cylinder turbo diesel. When I put my ear near the ground in front of the left front tire (driver's side), I can hear a steady rhythmic tick tick tick tick tick tick tick sound coming from the engine.

At first I thought it might be a loose crankshaft bolt on the front of the crankshaft causing the three spacer washers to sing a song. That said, I don't think it is that because the tick tick tick tick is in steady rhythmic time. You could set a metronome or watch to it.

All ideas and input is appreciated!!