SERVICE MANUAL CRANKSHAFT, MAIN BEARINGS, FLYWHEEL & CRANKCASE Section 6 Figure 14.  - Checking the Concentricity of the Flywheel Housing Bore in Relation to the Axis of the Crankshaft. Inspect the Crankcase as follows: 1. Check the crankcase deck for "PULLED" thread holes   which   may   interfere   with   the   head   and gasket  fit.    Lightly  file  these  areas  to  restore flatness. NOTE:  DO NOT resurface the block.  Any defects in the surface not correctable by light filing necessitates crankcase replacement. 2. Threaded  holes  with  damaged  threads  may  be salvaged with "Heli-Coil Repair."  3.400 Series Only:  Inspect the lower cylinder sleeve pilot bore for   erosion.      If   a   possibility   exists   that   water leakage  may  occur  from  erosion,  machine  the lower bore as follows: a. Rework the crankcase as shown in Fig. 15. Adhere to specified dimensions. IMPORTANT: Do Not Rework 300 Series Crankcases. Figure 15.  - Crankcase Rework Illustration for Lower Cylinder Sleeve Insert.  (400 Series Only) Symbol Dimension A (*)(.**) 125.83-125.88 mm (4.954-4.956 in) B 172.97-173.99 mm (6.810-6.850 in) C (-) 126.098-126.124 mm (4.9645-4.9655 in) D (*) (’) 122.38-1 22.43 mm (4.818-4.820 in) E 0.25 mm (0.010 in) R. Max. F 4.45 mm (0.175 in) G 33.66 mm (1.325 in) H 202.31 mm (7.965) * - Diameter to be concentric within 0.03 mm (0.001 inch) total indicator reading. **  -  Diameter  to  be  concentric  within  0.05  mm  (0.002 inch)  total indicator reading. ***  -  Center  line  to  be  square  with  crankshaft  bearing bores  within  0.08  mm  (0.003  inch)  in  305  mm  (12 inches). 4. Install a Lower Pilot Bore  insert as follows: a. Obtain  correct  bore  part  number  from  the parts catalog. b. Apply  "Locoquic  Primer  Grade  T"  (aerosol) completely  around  the  rebored  area  of  the block,  and  around  the  O.D.  of  the  repair insert. c. When  the  primer  is  dry  (approximately  30 seconds)  apply  "Loctite  Bushing  Mount"  to the O.D. of the repair insert. NOTE:    DO  NOT  wipe  off  any  primer  since  it  is  a catalyst    that    insures    the    proper    curing    of    the bushing mount. CGES-185-3 PRINTED IN UNITED STATES OF AMERICA Page 14