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ENGINE
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14.Install piston rings in their respective position on
piston using ring expander.
15.Stagger piston rings gaps such that they are
120°apart (with butt gap not in line with piston
pin)
CRANK SHAFT:
Clean and carry out visual inspection of crank shaft
for the following:
1. Overheating of journals, this is indicated by bluish
brown colour
2. Scoring marks on journals
3. Cracks, which should be checked on magnetic
crack detector
4. Check crank shaft run out by supporting it on V-
block at 1st and 5th main bearing journals.
5. If run out exceeds permissible limits, straighten
crank shaft in cold condition on press carefully.
6. Similarly check lateral and radial run outs of fly-
wheel mounting flange.
7. Check crank shaft main bearing and crank pin
journal dimension.
8. Record the readings in the format given at the
end of this group.
9. If necessary, grind crank shaft main bearing and
crank pin journals to next under-size.
10.Maintain correct fillet radius for journals
11.Care must be taken during grinding to ensure that
width of journals is not increased.
12.Should it be necessary to grind sides of 4th main
bearing journal, grind it to next undersize.
13.Re-chamfer oil holes on journals to avoid scoring
of new bearing shells.
14.Finish journals by lapping them with 320 grit lap-
ping cloth of suitable width.
15.After grinding recheck main bearing and crank pin
journal dimensions.