Engine Block and Piston Inspection

1.Remove the crankshaft and pistons.

2.Check the piston for distortion or cracks.

3.Measure the piston diameter at a point 14 mm (0.55 in.) from the bottom of the skirt.

Piston Diameter 
Standard (New): 80.980-80.990 mm
(3.1881-3.1886 in.)

Service Limit: 80.93 mm (3.186 in.) 

Oversize Piston Diameter 
0.25: 81.230-81.240 mm (3.1980-3.1984 in.) 



4.Measure the wear and taper Y at three levels inside each cylinder as shown. If the measurements in any cylinder are beyond the Oversize Bore Service Limit, replace the block. If the block is being rebored, refer to 7 after reboring.

Cylinder Bore Size 
Standard (New): 81.000-81.015 mm
(3.1890-3.1896 in.)
Service Limit: 81.070 mm (3.1917 in.) 

0.25: 81.250-81.265 mm (3.1988-3.1994 in.) 

Reboring Limit: 0.25 mm (0.01 in.) max. 

Bore Taper 
Limit: (Difference between first and third measurement) 0.05 mm (0.002 in.) 


5.Scored or scratched cylinder bores must be honed.

6.Check the top of the block for warpage. Measure along the edges, and across the center as shown.

Engine Block Warpage
Standard (New): 0.07 mm (0.003 in.) max. 
Service Limit: 0.10 mm (0.004 in.) 



7.Calculate the difference between the cylinder bore diameter and the piston diameter. If the clearance is near, or exceeds the service limit, inspect the piston and engine block for excessive wear.

Piston-to-Cylinder Bore Clearance
Standard (New): 0.010-0.035 mm
(0.0004-0.0014 in.)
Service Limit: 0.05 mm (0.002 in.)