Mitsubishi S4S Service Manual page 105

Unit: mm [in.]
Item
Nominal Assembly Service
Value Standard Limit
57.955
Crankpin 58 to 57.970 57.800
diameter [2.28] [2.2817 [2.2756]
to 2.2823]
Circularity 0.01
0.03
[0.0004]
Taper
or less
[0.0012]
(3) Grinding crankshaft
When grinding the crankpins and joumals, be
sure to produce the same fillet radius as the
original one. They should have a hardness of 620
or more in terms of Vickers Hardness Number.
If necessary, re-harden the crankpins and
journais, and inspeet them for cracks by
conducting a magnalux (magnetic particle) test.
ENGINE MAIN PARTS
Crankshaft grlnding dimensions
Unit: mm [in.]
Undersize
Grinding dirnension
0.25
77.705 to 77.720
[0.0098] [3.0593 to 3.0598]
Journal
0.50 77.455 to 77.470
[0.0197] [3.0494 to 3.0500]
0.75 77.205 to 77.220
[0.0295]
[3.0396 to 3.0402]
0.25 57.705 to 57.720
[0.0098] [2.2719 to 2.2724]
Crankpin
0.50
57.455 to 57.470
[0.0197] [2.2620 to 2.2626]
0.75 57.205 to 57.220
[0.0295] [2.2522 to 2.2528]
(4) Measuring crankshaft end play
(a) With the thrust plates installed in the front and
rear joumals and all bearing caps tightened
to the specified torque, measure the end play
(the difference in width between the joumal
and thrust plate). Ifthe end play exceeds the
repair limit, replace the thrust plate.
31+g
039
mm
[1.22+g
1H1 1 54
in.]
(b) If the end play still exceeds the repair limit
even after the new thrust plates have been
installed, replace the thrust plates with the
oversize ones. 0.15 mm [0.005 9 in.], 0.30
mm [0.011 8 in.] and 0.45 mm [0.017 7 in.]
oversize thrust plates are available for service.
Generally the rear joumal is likely to wear
more rapidly than the front joumal. This
means that replacement of the rear thrust
bearings will generally be sufficient.
Measuring crankshaft end play
7-43