CRANKSHAFT AND MAIN BEARINGS—H.3 To Remove the Crankshaft To   carry   out   this   operation,   it   will   be   necessary   to remove the engine from the application and mount it in a suitable dismantling stand. If   the   original   components   are   to   be   refitted   they should   be   suitably   marked   for   re-assembly   to   their original positions. 1. Remove  the  sump,  sump  strainer  and  the  oil  pump suction and delivery pipes. 2. Remove  the  timing  gears  and  timing  case.    (See Page K.3). 3. Remove   the   starter   motor,   flywheel   and   flywheel housing. 4. Remove   the   connecting   rod   caps   and   big   end bearings (See Page F.1). 5. Remove the rear main oil seal housing. 6. Take off the  rear main bearing bridge piece. 7. Remove  the  oil  pump  from  the  front  main  bearing cap (See Page L.3). 8. Remove main bearing cap setscrews. 9. Remove the main bearing caps and half bearings. 10. Lift  out  the  crankshaft  and  remove  the  other  half bearings. Fig. H.4. Exploded view of Crankshaft and Main Bearings. Regrinding the Crankshaft (see Data, Page H.8) Before  regrinding  the  crankshaft,  the  following  points should   be   checked   to   ensure   it   is   suitable   for   further machining. (a) The   crankshaft   should   be   crack-detected   before regrinding.    It  must,  of  course,  be  remembered  to demagnetize the crankshaft after crack detecting, in order  to  remove  any    polarization   which   may   be present. (b) The main journal and crankpin diameters should be checked  to  ascertain  the  next  appropriate  size  to which the crankshaft can be reground, i.e., —0.010 in (—0.25 mm),  —0.020  in  (—0,51 mm) or  —0.030 in  (  —0.76  mm).    If  the  crankshaft  requires  to  be reground     below     -0.030     in     (-0,76     mm)     it     is recommended that a new crankshaft be fitted.  See "Technical Data" for crankshaft regrind dimensions. (c) The  dimensions  given  in  "Technical  Data'  for  the crankpin  width  apply  only  to  a  standard  crankshaft. It   will   be   appreciated   that   this   dimension   may increase  as  the  crankpins  are  reground.    but  after regrinding  the  maximum  width  should  not  exceed 1,635   in   (41,53   mm).      During   regrinding,   all   the limits  must  be  adhered  to,  and  the  main  journals and crankpins must be free from grinding marks. After   regrinding,   the   sharp   corners   on   the   oil   holes should  be  removed  and  the  crankshaft  crack  detected again and demagnetized. Note:    It  is  important  that  the  radii  on  the main journals and crankpins are maintained.        If    these    are    neglected,   a fracture is liable to occur. To Refit the Crankshaft 1. Ensure all oilways are free from obstruction. 2. Check   the   main   bearing   setscrews   for   stretch   or damage    to    the    threads.        In    no    case    should setscrews  other  than  those  supplied  by  the  engine manufacturer be used as they are of a special  heat treated high grade steel.