PISTON INSPECTION
id011000502100
1. Measure the piston outer diameter using the micrometer.
The measurement position is 10.0 mm {0.40 in} from the lower end of the piston and in the thrust direction.
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• If it is not within the specification, replace the piston.
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Standard piston outer diameter
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87.465—87.495 mm {3.4435—3.4446 in}
2. Calculate the cylinder-to-piston clearance from the cylinder bore diameter and the piston outer diameter.
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• If the clearance is at the maximum specification or more, replace the piston or cylinder block.
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Clearance between piston and cylinder
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Standard
MZR 2.0 DISI, MZR 2.0 DISI i-stop : 0.0225—0.0475 mm {0.00089—0.00187 in}
MZR 2.3 DISI Turbo : 0.025—0.045 mm {0.0010—0.0017 in}
Maximum
0.11 mm {0.0043 in}
3. Measure the piston-to-ring groove clearance along the perimeter using a feeler gauge.
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• If the clearance is at the maximum specification or more, replace the piston or piston ring.
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Clearance between piston ring and ring groove
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Standard
Top : 0.04—0.08 mm {0.002—0.003 in}
Second : 0.03—0.07 mm {0.0012—0.0027in}
Oil: 0.02—0.06 mm {0.0008—0.0023 in}
Maximum
Top : 0.17 mm {0.0067 in}
Second, Oil : 0.15 mm {0.0059 in}
4. After inserting the piston ring into the cylinder, press in the piston ring to the position 42 mm {1.65 in} from the cylinder surface using the piston.
5. Measure the piston ring end gap using a feeler gauge.
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• If it is at the maximum specification or more, replace the piston ring.
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Piston ring end gap
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Standard
Top (MZR 2.0 DISI, MZR 2.0 DISI i-stop) : 0.16—0.26 mm {0.0063—0.010 in}
Top (MZR 2.3 DISI Turbo) : 0.14—0.24 mm {0.0056—0.0094 in}
Second (MZR 2.0 DISI, MZR 2.0 DISI i-stop) : 0.33—0.48 mm {0.013—0.018 in}
Second (MZR 2.3 DISI Turbo) : 0.34—0.44 mm {0.0134—0.0173 in}
Oil (rail) : 0.15—0.40 mm {0.0060—0.0157 in}
Maximum
1.0 mm {0.0393 in}
