TM    5-2815-241-34&P CYLINDER  HEAD  -  CONTINUED ACTION LOCATION ITEM REMARKS REPAIR/ASSEMBLY  -  CONTINUED NOTE Steps 26 through 31 are typical for all cylinder head valve seat Inserts tagged for replacement  or  previously  removed  during  cylinder  head  resurfacing. 26. Cylinder head (1) Valve   seat Insert  (2) If cylinder head has not been resurfaced, use  ST-1133  valve  seat  extractor  (3)  to remove valve seat inserts tagged for replacement. CAUTION Each replacement valve seat insert’s outside diameter and thickness must be measured and  compared  to  relating  valve  seat  counterbore  in  cylinder  head  before  counterboring. These measurements will prevent overboring and damage to the cylinder head. 27. 28. Valve   seat insert  (2) a. Using   2-to3-inch   micrometer, measure  outside  diameter. Record  reading  and  compare  to  spec- ifications in the following table. b.    Using  0-  to  1-inch  micrometer,  meas- ure  thickness. Record  reading  and  compare  to  spec- ifications in the following table. Valve   seat a. Using   depth   micrometer   (5),   measure counterbore    (4) depth  (6). NOTE Record  reading  and  compare  to  spec- ifications in the following table. b .    Using   inside   micrometer   (7),   measure inside  diameter. Record reading and compare to spec- ifications  in  the  following  table. After comparing measurements of removed valve seat insert and valve seat counterbore in cylinder head to the following table, choose the next oversize for replacement valve seat  insert,  and  counterbore  the  cylinder  head  to  dimensions  specified  for  that  oversize valve   seat   insert. 2-194