ELECTRICAL EQUIPMENT—Q.14 The commutator should be clean, entirely free from oil or   dirt.      Any   trace   of   such   should   be   removed   by pressing   a   clean   dry   fluffless   cloth   against   it,   while armature is hand rotated. If the commutator is dirty or discolored, tilt the brushes and wrap a strip of fine glass or carborundum paper (not emery  cloth)  round  the  commutator,  with  the  abrasive side  inwards.    Rotate  the  armature  by  hand  until  the surface is even.  Clean with a petrol moistened cloth. If repair is necessary to the commutator or switch gear etc.,   the   starter   must   be   dismantled.      This   should   be done only in accordance with the method given. DISMANTLING THE STARTER (Figs.  Q.9 and Q.10 refer). Remove  the  starter  from  the  engine,  and  proceed  as follows:- 1. Unscrew  the  shaft  lock-nut  (1)  (L.H.  thread  on clockwise rotation machine), remove pinion stop (2), shim washers (3) and return spring (4). 2. Remove   the   two   cover   screws   (55)   from   the drive-end  shield  and  unscrew  the  exposed  field coil terminal screws (54) and (58). 3. Remove the commutator end cover-band (26). 4. Unscrew  the  brush-lead  screws,  ease  off  brush springs  and  lift  brushes  from  the  holders.    Note that  removing  the  brush  screws  also  frees  the field coil and interconnector leads. 5. Remove the spring-clip (29) and take off the end cap (34). 6. Remove   the   circlip   (31),   thrust   washer   (30), shim-washers   (35),   steel   ball   (32)   and   spring (36). 7. Unscrew and withdraw the two throughbolts (37) from the commutator end-shield (27). 8. Remove   the   commutator   end-shield,   and   take off the shaft-shims (28). 9. The  yoke  (22),  pole-pieces  (23)  and  field  coils (24)   can   now   be   removed   as   one   assembly, leaving the armature completely exposed. 10. Unscrew  the  eight  pole-shoe  fixing  screws  (21) and   take   out   the   pole-pieces,   and   fieldcoils, taking  care  not  to  damage  the  leatheroid  (25), inserted between the coils and yoke. DISMANTLING THE OPERATING MECHANISM 1. Holding  the  pinion  (6)  and  drive-end  shield  (8) rigid, release the ball lock and withdraw the shaft from   the   pinion   sleeve   (44),   by   rotating   the armature in an anti-clockwise direction (clockwise on L.H. rotation machines). Note— This  may  require  a  little  more  than the normal force, because of probable   burring   resulting   from   the action of the ball lock.  Withdrawal of the  shaft  causes  the  four  steel  balls (16) to fall through to the inside of the pinion  sleeve,  and  these  should  now be recovered. 2. Using  circlip  pliers,  remove  the  circlip  (20)  from the pinion sleeve-end. 3. Remove   the   trip-collar   (19)   and   ball   locking collar  spring  (18).    Slide  off  the  locking  collar (17). 4. Withdraw the pinion (6). 5. Remove   the   two   screws   (51)   from   the   main terminal  connecting  link  (48).    Loosen  the  main terminal (47) and remove the link. 6. Remove   the   resistance   lead   (52)   from      the moving contact plate. 7. Remove  the  two  screws  (57)  holding  the  trip- gear  and  remove  by  threading  the trigger (40) through the slot in the moving contact plate. 8. Remove  the  two  screws  (50)  holding  the  stop plate and remove the plunger assembly (11).