Cummins 4BT – Piston Inspection

Inspect the piston for damage and excessive wear. Check the top, ring, grooves, skirt and pin bore.
NOTE: If severe piston damage has occurred, check the turbocharger and other exhaust components for damage
from debris.

Measure the piston skirt diameter as illustrated.

Use a new piston ring to measure the clearance in the ring groove.

Measure the pin bore.