Block and Piston Inspection

Remove the pistons from the engine block (see CRANKSHAFT AND PISTON REMOVAL ).
Check the pistons for distortion or cracks.
Measure the piston skirt diameter at a point 16 mm (0.63 in) from the bottom of the skirt.
Piston Diameter

Standard (New): 89.983-89.996 mm (3.54263-3.54314 in)

Service Limit: 89.975 mm (3.54232 in)

Fig 1: Measuring Piston Skirt Diameter
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Measure the wear and taper in direction X and Y at three levels in each cylinder as shown.
If the measurements in any cylinder are beyond the service limit or the cylinders are damaged, replace the engine block.
Cylinder Bore Size

Standard (New): 90.000-90.015 mm (3.54330-3.54389 in)

Service Limit: 90.065 mm (3.54586 in)

Bore Taper Limit: (Difference between first and third measurement) 0.05 mm (0.0020 in)

Fig 2: Measuring Cylinder Bore Wear And Taper
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check the top of the engine block for warpage. Measure along the edges and across the center as shown.
Engine Block Warpage

Standard (New): 0.07 mm (0.002 in) max.

Service Limit: 0.10 mm (0.003 in)

Fig 3: Identifying Engine Block Warpage
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 4: Measuring Engine Block Warpage
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Calculate the difference between cylinder bore diameter and the piston diameter. If the clearance is near or exceeds the service limit, inspect the piston and the cylinder bore for excessive wear.
Piston-to-Cylinder Bore Clearance

Standard (New): 0.004-0.032 mm (0.00016-0.00126 in)

Service Limit: 0.08 mm (0.0031 in)

Fig 5: Identifying Piston-To-Cylinder Bore Clearance
Courtesy of AMERICAN HONDA MOTOR CO., INC.