TM 10-3930-659-34 4-12. ENGINE ROCKER ARM ASSEMBLY AND PUSHRODS MAINTENANCE (Con’t). 3. Inspect shaft for severe scratching, scoring, or excessive wear at points of engine rocker arm contact.  Replace shaft if damaged. 4. Roll    shaft    on    flat    surface    to    check    for    bends    and    distortion.        Replace    shaft    if    bent    or    distorted. 5. Using  outside  caliper  micrometer,  measure  out- side diameter of shaft at each engine rocker arm location.      If   outside   diameter   is   smaller   than 0.785 in.  (19.939 mm), replace shaft. 6. Using inside caliper micrometer, measure inside diameter   of   six   shaft   supports   (10).      If   inner diameter  is  more  than  0.794  in.    (20.168  mm), replace shaft supports. 7. Using inside caliper micrometer, measure inside diameter of 12 engine rocker arms (13).  If inside diameter  is  more  than  0.794  in.    (20.168  mm), re- place engine rocker arm. 8. Inspect  12  engine  rocker  arms  for  cups  and  concave  wear  on  ends  where  contact  is  made  with  cylinder  head valve tips.  Replace engine rocker arms if worn. 9. Using spring tester and torque wrench, compress five springs to 1.81 in.  (4.60 cm) and note compression force on torque wrench.  Compression force must be 4-6 lb.-ft.  (5-8 N-m).  Replace spring if defective. 10. Roll 12 pushrods on flat surface to check for bends or distortions.  Replace pushrod if bent or distorted. TA708096 4-57