Block & Piston Inspection: Notes

Remove the piston from the cylinder block. See CRANKSHAFT & PISTON (REMOVAL & INSTALLATION) .
Check the piston for distortion or cracks.

Measure the piston diameter at a point .63" (16 mm) from the bottom of the skirt. See Fig 1 and PISTON & OVERSIZE PISTON DIAMETER table.

PISTON & OVERSIZE PISTON DIAMETER

Measure wear and taper in directions X and Y at three levels in each cylinder bore. See Fig 2.

If the measurements in any cylinder are beyond the oversize bore service limit, replace the cylinder block.
If the block is to be rebored, see step 6 after reboring.

CYLINDER BORE SIZE/OVERSIZE/BORE TAPER

Application

Specification - In. (mm)

Cylinder Bore Size

Standard (New)

.3.5039-3.5045 (89-89.015)

Service Limit

3.5065 (89.065)

Oversize

.25

3.5138-3.5144 (89.250-89.265)

.50

3.5236-3.5242 (89.500-89.515)

Reboring Limit

.02 (.5)

Bore Taper

Limit ⁽¹⁾

.002 (.05)

⁽¹⁾	Difference between first and third measurement.

Check the top of the cylinder block for warpage. Measure along the edges and across the center. See Fig 3 and CYLINDER BLOCK WARPAGE table.

CYLINDER BLOCK WARPAGE

Application	Specification - In. (mm)
Standard (New)	.003 (.07)
Service Limit	.004 (.10)

Calculate the difference between cylinder bore diameter and piston. See Fig 4 and PISTON-TO-BLOCK CLEARANCE table.

PISTON-TO-BLOCK CLEARANCE

Application	Specification - In. (mm)
Standard (New)	.0006-.0016 (.015-.040)
Service Limit	.003 (.08)

Fig 1: Measuring Piston Diameter At Point From Bottom Of Skirt

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 2: Measuring Cylinder Bore Wear & Taper

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 3: Checking Cylinder Block Warpage

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 4: Identifying Piston-To-Bore Clearance

Courtesy of AMERICAN HONDA MOTOR CO., INC.