Piston-To-Bore Clearance

WARNING: This page is about a different car, the 2004 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.

Using a bore gauge, measure cylinder bore for wear, out-of-round and taper. The Y axis is in the longitudinal direction of the engine.
1. Standard inner diameter (Grade No. 1) : 80.000 - 80.010 mm (3.1496 - 3.1500 in)
2. Wear limit : 0.2 mm (0.008 in)
3. Out-of-round (X - Y) standard : Less than 0.015 mm (0.0006 in)
4. Taper (B - A) standard : Less than 0.01 mm (0.0004 in)
If it exceeds the limit, rebore all cylinders. Replace cylinder block if necessary.

Fig 1: Measuring Cylinder Bore For Wear, Out-Of-Round And Taper
Courtesy of NISSAN MOTOR CO., U.S.A.
Check for score and seizure. If seizure is found, hone it.
NOTE: If cylinder block or piston is replaced, match piston grade with grade number on cylinder block lower surface.

Fig 2: Identifying Cylinder Bore Grade Number
Courtesy of NISSAN MOTOR CO., U.S.A.
Measure piston skirt diameter.
1. Piston diameter "A" : Refer to "PISTON, PISTON RING AND PISTON PIN ".
2. Measuring point "a" (Distance from the top): 42.3 mm (1.665 in)
Fig 3: Measuring Piston Skirt Diameter
Courtesy of NISSAN MOTOR CO., U.S.A.
Check that piston-to-bore clearance is within specification.
1. Piston-to-bore clearance = cylinder bore measurement "B" - Piston diameter "A" : 0.025 - 0.045 mm (0.0010 - 0.0018 in)
Determine piston oversize according to amount of cylinder wear.
- Oversize pistons are available for service. Refer to "PISTON, PISTON RING AND PISTON PIN ".
Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter "A".
Rebored size calculation

D = A + B - C
1. where:
  1. D : Bored diameter
  2. A : Piston diameter as measured
  3. B : Piston-to-bore clearance
  4. C : Honing allowance 0.02 mm (0.0008 in)
Install main bearing caps and tighten bolts to the specified torque. This will prevent distortion of cylinder bores.
Cut cylinder bores.
- When any cylinder needs boring, all other cylinders must also be bored.
- Do not cut too much out of cylinder bore at a time. Cut only 0.05 mm (0.0020 in) or so at a time.
Hone cylinders to obtain specified piston-to-bore clearance.
Measure finished cylinder bore for out-of-round and taper.
- Measurement should be done after cylinder bore cools down.