D21- Clicking, smoking, skipping- intermittently

Komatsu D21-6, changed waterpump, ran it hard for a few days cutting fireline in the marsh. It ran perfectly, temp gauge stayed in the lower half of normal, lost no water, sounded great. Brought it home and left it on the trailer for about a week. I needed the truck for something else, so I checked the fluids and started it. As soon as it started, it started clicking, almost like a lifter tapping, skipping, and blowing a thin blue-gray smoke. I ignored the smoke, (because I had just started...

D21- Clicking, smoking, skipping- intermittently

D21- Clicking, smoking, skipping- intermittently