Block and Piston Inspection

Remove the crankshaft and pistons (see OIL PAN REMOVAL ).
Check the piston for distortion or cracks.
Measure the piston diameter at a point 16 mm (0.6 in.) (2000-2003 models), or 10 mm (0.4 in.) (2004-2008 models) from the bottom of the skirt. There are two standard-size pistons (No Letter or A, and B). The letter is stamped on the top of the piston. Letters are also stamped on the engine block as cylinder bore sizes.
Piston Diameter

Standard (New):

No Letter (or A): 86.993-87.006 mm (3.4249-3.4254 in.)

B: 86.983-86.996 mm (3.4245-3.4250 in.)

Service Limit:

No Letter (or A): 86.980 mm (3.4244 in.)

B: 86.970 mm (3.4240 in.)

Oversize Piston Diameter

0.25: 87.233-87.246 mm (3.4344-3.4349 in.)

Fig 1: Measuring Piston Diameter
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove all of the old liquid gasket from the lower block mating surfaces, bolts, and bolt holes.
Clean the lower block mating surfaces.
Put the lower block on the engine block.
Tighten the bearing cap bolts in sequence to 29 N.m (3.0 kgf.m, 22 lbf.ft).

Fig 2: Identifying Tightening Sequence Of Bearing Cap Bolts
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Tighten the bearing cap bolts an additional 60 °.

Fig 3: Identifying Bearing Cap Bolts Additional Tightening Angle
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 measurements in any cylinder are beyond the oversize bore service limit, replace the engine block. If the block is to be rebored, refer to step 12 after reboring.
Cylinder Bore Size

Standard (New)

A or I: 87.010-87.020 mm (3.4256-3.4260 in.)

B or II: 87.000-87.010 mm (3.4252-3.4256 in.)

Oversize

0.25: 87.250-87.260 mm (3.4350-3.4354 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.)

Fig 4: Identifying Cylinder Bore Taper And Wear Measurement Levels
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Scored or scratched cylinder bores must be honed.
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.)

Fig 5: Checking Top Of Cylinder Block For Warpage
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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 Clearance

Standard (New): 0.004-0.027 mm

(0.0002-0.0011 in.)

Service Limit: 0.004 mm (0.0002 in.)

Fig 6: Identifying Difference Between Cylinder Bore Diameter And Piston Diameter
Courtesy of AMERICAN HONDA MOTOR CO., INC.