ARMY TM 9-2815-256-24 AIR FORCE TO 38G1-96-2 MARINE CORPS TM 2815-24/5 Section XIII.  IDLER GEARS AND FRONT PLATE ASSEMBLY MAINTENANCE 3-41.  IDLER GEARS AND SHAFTS 3-41.1.  Removal. a. Remove timing gear cover, refer to paragraph 3-39.1. b. Remove oil pan, refer to paragraph 3-20.1. c. Remove front crankshaft sleeve bearing  (8, FIGURE 3-137), preformed packing (9), and dirt deflector (10). d. Measure idler gear end play, refer to paragraph 3-41.2. e. Measure idler (timing) gear backlash, refer to paragraph 3-41.2. f. Remove bolt (1, FIGURE 3-134) and thrust washer (2) securing upper idler gear (3) to shaft (5); remove idler gear (3). g. Remove nut (8) and thrust washer (10) securing lower idler gear (11); remove idler gear (11). h. If necessary, use an arbor press and remove bearings (4 and 12) from gears (3 and 11). i. Remove bolt (13) and washer (14) from lower idler gear shaft (15). j. Remove lower idler gear shaft (15) from front plate by using a pry bar.  Remove thrust washer (9).  A k. Remove upper idler gear shaft (5) from front plate by using a pry bar.  Remove thrust washer (7). I. Remove spring pins (6 and 16) from shafts. 3-41.2.  Inspect and Measure. a. Measure idler gear end play as follows: (1) Using a dial indicator, check end play of upper and lower idler gears. (2) New end play is 0.006 to 0.012 inch (0.14 to 0.29 mm), and maximum acceptable is 0.016 inch (0.40 mm). b. Using a dial indicator, measure backlash between timing gears.  Specification given is for new parts. (1) Camshaft to upper idler 0.003 to 0.014 inch (0.07 to 0.35 mm). (2) Injection pump to upper idler 0.003 to 0.014 inch (0.07 to 0.35 mm) (3) Upper idler to crankshaft 0.003 to 0.012 inch (0.07 to 0.30 mm). (4) Crankshaft to lower idler 0.003 to 0.014 inch (0.07 to 0.35 mm). (5) Oil pump to lower idler 0.0016 to 0.015 inch (0.04 to 0.36 mm). (6) If backlash is not within specification, install new gears. Change 3 3-174