Xterra XE 4WD V6-3.3L SC (VG33ER) (2002)
Valve Seat: Testing and Inspection
VALVE SEATS
Check valve seats for any evidence of pitting at valve contact surface, and reseat or replace if it has worn out excessively.
Before repairing valve seats, check valve and valve guide for wear.
If they have worn, replace them. Then correct valve seat.
Use both hands to cut uniformly.