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(b) Ensure (hat the flywheel locating key is replaced in the crankshaft
before fitting the flywheel
(c) A new tabwasher must be fitted before tightening the flywheel retaining
nut. Tighten the flywheel nut using a torque spanner set to the figure
shown under Technical Data
(d) When the nut is tight, knock up the tabwasher
(e) If a 4 1 hand starting arrangement is fitted, the gearwheels should be
greased and the sliding plate, locating screws and the starting handle
shaft recess oiled Tighten the flywheel extension gearwheel bolts using
a torque spanner set to the figure shown under Technical Data.
51. To remove crankshaft
(a) Remove the cylinder head. cylinder, connecting rod and flywheel
(b) Remove any starting arrangement or fitting from the gear cover
(c) AC1W. Remove the main bearing housing oil pipe.
(d) Remove the gear cover The cover is dowelled to the crankcase.
(e) Remove the crankshaft extension shaft at the gear end. if fitted
(f) Remove the crankshaft gearwheel retaining bolt Withdraw the
gearwheel with a simple extractor.
(g) Remove the nuts retaining the flywheel end main bearing housing.
Remove the housing taking care not to damage the oil seal
(h) Withdraw the crankshaft by pulling towards the flywheel end.
52. Crankshaft maintenance
(a) Carefully examine the bearing journals and crankpin They should be
free from score marks and ovality should not exceed the maximum
(see Technical Data).
(b) If these defects are present the crankshaft should be reground to the
diameter shown under Technical Data and undersize bearings fitted
(c) Carefully clean out the oil holes and make sure they have radiused
edges.
53. Main bearing maintenance
(a) Main bearings are of the precision thin wall steel backed sleeve type
lined with bearing metal
(b) When removing a gear end bearing from the crankcase or a flywheel
end bearing from the bearing housing, heal the crankcase or bearing
housing to a temperature of 93/120°C (200/250°F) be fore pressing out
the bearing
(c) When fitting a bearing, the crankcase or bearing housing should again
be heated as above and the outer surface of the bearing should be
smeared with molybdenum-disulphide grease or tallow before pressing
in It is an advantage if the bearing can be placed in a domestic type
refrigerator for a time before fitting
(d) Do not remove the bearings unnecessarily or their tightness in the
crankcase or bearing housing may be affected It is not advisable to
remove the bearings more than five times
(e) When fitting a bearing take care that it enters squarely.
(f) New bearings are machined to give the required fit when in position and
should not be scraped or bedded in. neither should shims of any
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