Royal Enfield CONSTELLATION 1958, Руководство по техническому обслуживанию мастерской

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Turn the crankshaft until the connecting rods
are at bottom dead centre and the two halves of
the crankcase can then be separated, tapping the
crankcase with a soft mallet.
The inner race of the roller bearings on the
timing side will remain on the crankshaft
bringing with it the cage and rollers and leaving
the outer face fixed to the crankcase.
The inner race of the ball bearing on the
driving side is a tight fit on the shaft and can be
removed with Special Tool No. E.5121. If this is
not available, the shaft can be driven out with a
hide mallet or a soft metal drift.
To avoid damage to the ball bearing the case
should be heated to about 100°C. before doing
this.
4. Main Bearings
To remove the ball bearing from the driving
side crankcase, heat the crankcase to about 100
degrees C. by immersion in hot water or in an
oven after which the bearing can be driven out
using a drift
which applies pressure to the
outside race only.
When refitting a new ball bearing, heat the
crankcase in the same way and use the same
drift taking great care to keep the bearing square
with the bore.
To remove the outer roller race from the
timing side crankcase, first heat the crankcase
then drive the race out using a small punch
through the three holes provided.
The inner race and rollers can be withdrawn
from the crankshaft using a claw type extractor.
When refitting the inner race drive it on to
the shaft until just flush with the end and no
further.
5. Fitting the Connecting Rods
To remove the connecting rods from the
crankshaft, first take out the cotter pins securing
the socket screws in the connecting rods and
then remove the socket screws themselves.
If the big end bearing caps are removed to
examine the condition of the bearings, make
sure that the caps are refitted the same way
round on the same rods and that the rods
themselves are refitted the same way round on
the same crank pins.
In refitting the connecting rods, the socket
screws should be tightened with a torque
wrench set at 200-220 inch-lbs.
If the cotter pins do not come in line remove
the socket screws and use a different thickness
of washer. A difference of .005 in. in the washer
alters the position of the screw approximately
1/8 of a turn.
There is a recess in one side of the
connecting rod for a cotter pin head and this
side must face outwards when the connecting
rod is assembled on the crankshaft to avoid
fouling between the cotter and the crankshaft
web.
If it is necessary to replace the big ends, a
service crankshaft can be supplied with
connecting rods fitted.
6. Re-assembly of the Crankcase
Fit the outer roller race in the timing side
crankcase, the ball-bearing in the driving side
crankcase and the inner roller race on the crank-
shaft as described in Subsection 4.
Be sure that the inner race is driven on just
flush with the end of the crankshaft and no
further.
There are several methods of assembling the
crankcase. If the timing-side is fitted to the
crankshaft first, care must be taken not to score
the inside of the case. If the driving-side is
fitted first
it is possible, with some makes of
roller bearing, though not probable, to drop one
of the rollers into the crankcase and cause
serious damage to the engine.
(a) Timing-side First. Heat the timing-side
crankcase with the outer roller bearing race in
position to about 100° C.
Lay the crankcase flat on the bench and
insert the shaft, with the inner roller race in
position, arranging the connecting rods so that
they do not foul the crankcase.
Insert the camshafts in their correct position
(exhaust front, inlet rear).
Put the distance piece in position on the
driving side of the crankshaft.
Apply jointing compound to the timing side
crankcase.
Heat the driving-side crankcase and bearing
to 100° C. and drop it over the crankshaft,
making sure to lift the tappets clear of the cams.
Bolt the two halves of the crankcase
together. The crankshaft should now be drawn
into its correct position by fitting the engine
sprocket temporarily and tightening the nut
whilst the crankcase is still hot.
(b) Driving-side First. Support the
crankshaft with the driving end pointing
upwards and place the distance piece in
position. Heat the drivingside crankcase to
about 100° C. and place it over the crankshaft.
Fit the engine sprocket and tighten the nut
while the crankcase is still hot.
Invert the crankshaft and crankcase and sup-
port it on two blocks of wood or a large block
with a hole in it.
Insert the camshafts in their correct position
(exhaust front, inlet rear).
Apply jointing compound to the driving-side
crankcase.
Heat the timing-side crankcase (with the
outer roller race) to about 100° C. and drop it
Section D10 Page 2
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