Cylinder Bore; Oil Jet - Mazda MX-5 1990 Workshop Manual

INSPECTION I REPAIR
B
c--t--L-
05UOBX-150
05UOBX-151
05UOBX-152
•
05U08X-154
4_ Measure the cylinder bores in X and Y directions at three
levels (A, B, and C) in each cylinder as shown.
Cylinder bore
mm (in)
Bore size Diameter
Standard 78.006-78.013 (3.0711-3.0714)
0.25 (0.010) oversize 78.256-78.263 (3.0809-3.0812)
0.50 (0.020) oversize 78.506-78.513 (3.0908-3.0911)
Caution
• The boring size should be based on the size of an
oversize piston and be the same for all cylinders.
(1) If the cylinder bore exceeds the maximum, rebore the
cylinder to oversize.
(2) If the difference between measurements A and C ex-
ceeds the maximum taper, rebore the cylinder to
oversize.
Taper: 0.019mm (0.0007 in) max.
(3) If the difference between measurements X and Y ex-
ceeds the maximum out-at-round, rebore the cylinder
to oversize.
Out-of-round: 0.019mm (0.0007 in) max.
5. If the upper part of a cylinder wall shows uneven wear, re-
move the ridge with a ridge reamer.
OIL JET
1. Push the check ball and verify that it moves smoothly.
2. Blow through the oil jet and verify that air flows .
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