TM  5-2815-241-34&P FUEL INJECTOR - CONTINUED ACTION LOCATION ITEM REMARKS INSPECTION  -  CONTINUED 15. Injector  cup  (1) a. Using  magnifying  glass,  and  comparing with new injector cup (1), inspect injec- tor cup for abrasive wear, corrosion damage,  and  enlarged  or  distorted spray holes. If  abrasive  wear,  corrosion  damage, or  enlarged  or  distorted  spray  holes exist,  replace  Injector  cup. b. Using prussian blue on a new plunger, insert plunger into injector cup (1) and rotate  90  degrees. If  plunger  seat  pattern  in  Injector  cup does  not  cover  a  40-percent  continu- ous  area  around  the  injector  cup cone,  as  illustrated  below,  replace injector  cup. CONTINUOUS   PATTERN STAR   PATTERN BROKEN   PATTERN GOOD   SEAT BAD  SEAT BAD  SEAT c. Using  lapping  plate  and  cutting  fluid,  lap slightly  to  check  injector  cup  barrel  sur- face  for  mutilation  and  flatness  in  the areas  shown  by  black  in  the  illustration below. After lapping slightly, if mutilation or unevenness  exists,  replace  Injector cup. T A    2 4 2 5 7 9 2-360