TM 10-3930-659-34 4-19.  ENGINE OIL PUMP REPLACEMENT (Con’t). 6. Using     outside     caliper     micrometer,     measure outside  diameter  of  long  end  (14)  of  drive  shaft spur gear (3).  Minimum allowable measurement is 0.629 in.  (15.9766 mm). 7. Using     outside     caliper     micrometer,     measure outside diameter of short end (13) of drive shaft spur gear (3).  Minimum allowable measurement is 0.4815 in.  (12.2301 mm). 8. Using inside caliper micrometer, measure inside diameter  of  drive  shaft  spur  gear  bore  (15)  of engine    oil    pump    (2).        Maximum    allowable measurement is 0.4850 in.  (12.3190 mm). 9. Install   drive   shaft   spur   gear   (3)   in   engine   oil pump (2). 4-78