Cylinder Block

Remove the gasket material. Using a gasket scraper, remove all the gasket material from the top surface of the cylinder block.
Clean the cylinder block. Using a soft brush and solvent, thoroughly clean the cylinder block.
Inspect the top surface of cylinder block for flatness. Using a precision straight edge and feeler gauge, measure the surface contacting the cylinder head gasket for warpage.
Flatness of cylinder block gasket surface

Total: Less than 0.05 mm (0.0020 in)

Bore to bore: Less than 0.03 mm (0.0012 in)

Fig 1: Measuring Cylinder Block Flatness
Courtesy of KIA MOTORS AMERICA, INC.
Inspect the cylinder bore. Visually check the cylinder for vertical scratches. If deep scratches are present, replace the cylinder block.
Inspect the cylinder bore diameter. Using a cylinder bore gauge, measure the cylinder bore diameter at position in the thrust and axial direction.
Standard diameter: 82.00-82.03 mm (3.2283-3.2295 in)

Fig 2: Measuring Cylinder Bore Diameter
Courtesy of KIA MOTORS AMERICA, INC.
Check the cylinder bore size code on the cylinder block bottom face.

Fig 3: Identifying Cylinder Bore Size Code
Courtesy of KIA MOTORS AMERICA, INC.

Fig 4: Identifying Cylinder Bore Size Chart
Courtesy of KIA MOTORS AMERICA, INC.
Check the piston size mark (A) on the piston top face.

Fig 5: Identifying Piston Size Location
Courtesy of KIA MOTORS AMERICA, INC.

Fig 6: Identifying Piston Outer Diameter Chart
Courtesy of KIA MOTORS AMERICA, INC.
Select the piston related to cylinder bore class.
Piston-to-cylinder clearance: 0.02-0.04 mm (0.0008-0.0016 in)