BSA D14/4 BANTAM SUPREME D14/4 BANTAM SPORTS, Руководство по ремонту

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D14/4 ENGINE B8
Before starting work on a complete strip-down of
the engine unit it is advisable to have the following
tools and replacements available.
(1 off) 00-3311 Gasket set
(3 off) 90-0749 Oil seal
(1 off) 90-0147 Oil seal
(2 off) 57-3621 Main bearing
(1 off) 90-0010 Main bearing
(2 off) 90-1386 Gudgeon pin circlip
The following service tools are also needed.
61-3191 Clutch spring compressor
61-3786 Engine sprocket extractor
If any difficulty is encountered in unscrewing the nut,
apply a few drops of penetrating oil to the threaded
portion and allow to soak before attempting to
unscrew it any further.
Disconnect the contact breaker lead at the snap
connecter under the primary chaincase. The gearbox
should now be drained by removing the filler and drain
plugs and allowing the oil to drain into a suitable
receptacle.
Detach the sparking plug lead, and disconnect the
generator leads at their snap connectors. The clutch
cable should now be disconnected as detailed in D12.
Remove the chainguard as detailed on page D9, and
take off the rear chain, noting the correct fitting of the
spring link,
i.e., closed end pointing forwards on top
run of chain.
Unscrew the two bolts fixing the petrol tank at the
front and loosen the rear fixing bolt. The tank can now
be raised slightly to provide sufficient clearance of the
engine.
The engine is held in the frame by two nuts and
bolts and the front and two at the rear. One of the rear
fixing bolts is situated beneath the engine.
Remove the four fixing bolts and carefully lift the
engine out of the frame.
When a prop stand has been fitted as an optional
extra (not applicable to Bushman models), it will be
released on removal of the front fixing bolts. On
Bushman models, the front fixing bolts also retain the
crankcase shield.
The kickstart and gearchange pedals can now be
taken off in preparation for engine dismantling,
described below.
ENGINE DISMANTLING
Perfect cleanliness is essential to ensure the success of
any service task, so before starting work make sure
you have a clean bench or working area in which to
operate, and somewhere to place the parts as they are
removed.
The following notes give in detail the correct
procedure for dismantling the engine/gearbox unit.
It will be assumed that the engine unit has been
drained of oil, removed from the frame, and
dismantled for decarbonising as described in the
previous pages.
The primary cover is held in place by five Phillips-
head screws, each of which is fitted with a fibre
washer. It is not necessary the oil level screw, painted
red. Place a suitable tray under the joint to catch any
oil, and gently tap the cover with a hide-mallet to
break the joint.
The primary cover can now be lifted away complete
with the contact breaker cover which is held in place
by two screws. Mark the position of the contact
breaker plate in relation to the case with a scriber to
assist assembly. Remove the plate fixing screws, and
contact breaker mounting plate.
Carefully unscrew the contact breaker cam screw on
the end of the drive shaft. Before the screw reaches the
end of its thread the head will bear against the circlip
and further rotation of the screw should release the
cam from its taper. It may, however be necessary to
lightly tap the cam to free it from the taper.