Sunbeam ALPINE I SERIES: APLINE II SERIES, Workshop Manual

Page: 337 / 413

WSM.124
Section N (Elec. Equip.)
I st re-Issue
Page 19
STARTER DRIVE
GENERAL
The pinion and barrel assembly Is mounted on a
screwed sleeve, which Is carried on splines on the
armature shaft. The sleeve is so arranged that It
can move along the shaft against a compression
spring to reduce the shock loading at the moment
engagement takes place.
When the starter switch is operated the armature
shaft and screwed sleeve rotate. Owing to the
Inertia of the pinion and barrel assembly the latter
Is caused to move along the sleeve until the pinion
comes Into engagement with the flywheel ring.
The starter will then turn the engine.
As soon as the engine fires and commences to run
under Its own power the flywheel will be driven
faster by the engine than the starter. This will
cause the pinion and barrel assembly to be screwed
back along the sleeve, so drawing the pinion out
of mesh with the flywheel teeth. In this manner
the drive safeguards the starter against damage
due to being driven at high speeds.
A pinion restraining spring is incorporated In the
drive. This spring prevents the pinion vibrating
Into mesh when the engine Is running.
ROUTINE MAINTENANCE
If any difficulty Is experienced with the starting
motor not meshing correctly with the flywheel, It
may be that the drive requires cleaning. The
pinion and barrel assembly should move freely on
the screwed sleeve; if there Is any dirt or other
foreign matter on the sleeve It must be washed off
with paraffin.
In the event of the pinion becoming Jammed In mesh
with the flywheel, it can usually be freed by turning
the starter motor armature by means of a spanner
applied to the shaft extension at the commutator
end.
DISMANTLING AND REASSEMBLY
Having removed the armature as described In the
section dealing with starting motors, the drive can
be dismantled as follows (see Fig.
18):-
Remove the split pin (A) from the shaft nut
(B)
at the end of the starter drive. Hold the squared
starter shaft extension at the commutator end by
means of a spanner and unscrew the shaft nut
(B).
Lift off the main spring (C) and buffer washer (D)
and remove the retaining ring (E) from Inside the
end of the pinion and barrel assembly
(F).
Corru­
gated washer (L), control nut (G), sleeve (H) and
restraining spring
(J)
will now slide off. Withdraw
the splined washer (K) from the armature shaft and
remove the pinion and barrel.
The assembly of the drive Is a reversal of the
dismantling procedure.
Note.-Should either the control nut or screwed
sleeve be damaged, then a replacement assembly
of screwed sleeve and control nut must be fitted.
These components must not be renewed lndlvldually.
Fl1.
18.
Exploded view
of
starter drive