Block and Piston Inspection
WARNING: This page is about a different car, the 2006 Acura MDX, 2005 Acura MDX, 2004 Acura MDX, and 2003 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.
- Remove the piston from the engine block (see CRANKSHAFT AND PISTON REMOVAL ).
- Check the piston for distortion or cracks.
- Measure the piston diameter at a point 16.0 mm (0.63 in.) from the bottom of the skirt.
Piston Diameter
- Standard (New): 88.975-88.985 mm (3.5029-3.5033 in.)
- Service Limit: 88.965 mm (3.5026 in.)
Oversize Piston Diameter
- 0.25: 89.225-89.235 mm (3.5128-3.5132 in.)
- Measure wear and taper in direction X and Y at three levels in each cylinder as shown in Fig 2
. If measurements in any cylinder are beyond the oversize bore service limit, replace the engine block. If the engine block has to be rebored, refer to step 7
after reboring.
Cylinder Bore Size
- Standard (New): 89.000-89.015 mm (3.5039-3.5045 in.)
- Service Limit: 89.065 mm (3.5065 in.)
Oversize
- 0.25: 89.250-89.265 mm (3.5138-3.5144 in.)
- Reboring Limit: 0.25 mm (0.01 in.)
Bore Taper
- Limit: (Difference between first and third measurement) 0.05 mm (0.002 in.)
- Hone any scored or scratched cylinder bores.
- Check the top of the engine block for warpage. Measure along the edges and across the center as shown in Fig 3
.
Engine Block Warpage
- Standard (New): 0.07 mm (0.003 in.) max.
- Service Limit: 0.10 mm (0.004 in.)
- Calculate the difference between cylinder bore diameter and 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): 0.015-0.040 mm (0.0006-0.0016 in.)
- Service Limit: 0.08 mm (0.003 in.)