LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Acura >> 2007 >> CSX Type-S >> Repair and Diagnosis >> Engine Mechanical >> Mechanical >> Engine Block >> Block and Piston Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Block and Piston Inspection

  1. Remove the crankshaft and pistons (see CRANKSHAFT AND PISTON REMOVAL  ).
  2. Check the piston for distortion or cracks.
  3. Measure the piston diameter at a point 11 mm (0.4 in.) 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): 85.980-85.990 mm (3.3850-3.3854 in.) 

    B: 85.970-85.980 mm (3.3846-3.3850 in.) 

    Service Limit: 

    No Letter (or A): 85.930 mm (3.3831 in.) 

    B: 85.920 mm (3.3827 in.) 

    Oversize Piston Diameter 

    0.25: 86.230-86.240 mm (3.3949-3.3953 in.) 

    Fig 1: Measuring Piston Diameter
    G06264360Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Measure the wear and taper in direction X and Y at three levels inside each cylinder as shown. If the measurements in any cylinder are beyond the Oversize Bore Service Limit, replace the engine block. If the engine block is being rebored, refer to step  7 after reboring.

    Cylinder Bore Size 

    Standard (New): 

    A or I: 86.010-86.020 mm (3.3862-3.3866 in.) 

    B or II: 86.000-86.010 mm (3.3858-3.3862 in.) 

    Service Limit: 86.070 mm (3.3886 in.) 

    Oversize Bore 

    0.25: 86.250-86.260 mm (3.3957-3.3961 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 2: Measuring Wear And Taper Of Cylinder Bore
    G06264361Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Scored or scratched cylinder bores must be honed.
  6. 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 (0.003 in.) max. 

    Service Limit: 0.10 mm (0.004 in.) 

    Fig 3: Checking Top Of Engine Block For Warpage
    G06264362Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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 cylinder bore for excessive wear.

    Piston-to-Cylinder Bore Clearance 

    Standard (New): 0.020-0.040 mm (0.0008-0.0016 in.) 

    Service Limit: 0.05 mm (0.002 in.) 

    Fig 4: Identifying Piston-To-Cylinder Bore Clearance
    G06264363Courtesy of AMERICAN HONDA MOTOR CO., INC.