Repair Procedures: Inspection: Piston

1. Clean the piston.
   1. Using a gasket scraper, remove the carbon from the piston top.
   2. Using a groove cleaning tool or broken ring, clean the piston ring grooves.
   3. Using solvent and a brush, thoroughly clean the piston.
   NOTE:

   • Do not use a wire brush.
2. Check the piston-to-cylinder clearance by calculating the difference between the cylinder bore inner diameter and the piston outer diameter.

   Piston-To-Cylinder Clearance: 

   0.03 - 0.05 mm (0.0012 - 0.0020 in)

   1. Using a cylinder bore gauge, measure the cylinder bore diameter at position in the thrust and axial direction.

      Cylinder Bore Diameter: 

      77.00 - 77.03 mm (3.0315 - 3.0327 in)

      Courtesy of HYUNDAI MOTOR AMERICA

   2. Measure the piston outside diameter at 12 mm (0.4724 in) from top land of the piston.

   Piston Outside Diameter: 

   76.96 - 76.99 mm (3.0299 - 3.0311 in)

   Courtesy of HYUNDAI MOTOR AMERICA

3. Select the piston matching with cylinder bore class.

   Piston-To-Cylinder Clearance: 

   0.03 - 0.05 mm (0.0012 - 0.0020 in)

1. Check the cylinder bore size mark on the side of the cylinder block.

   Courtesy of HYUNDAI MOTOR AMERICA

   Discrimination Of Cylinder Bore Size 

   Mark	Cylinder Bore Inner Diameter
   A	77.00 - 77.01 mm (3.0315 - 3.0319 in)
   B	77.01 - 77.02 mm (3.0319 - 3.0323 in)
   C	77.02 - 77.03 mm (3.0323 - 3.0327 in)

2. Check the piston size mark on the piston top face.

Courtesy of HYUNDAI MOTOR AMERICA

Piston Outer Diameter Difference