FIGURE 3-21. Front Gear Train Backlash Measurement.
(2) Rotate gear clockwise. Position indicator to "0".
(3) Rotate gear counterclockwise. Verify indicator reading is between 0.003 inch (0.07 mm) and 0.020
inch (0.51 mm).
If backlash is not within specifications, be sure the
adjacent (engaging) gear is not moving during the
(4) If reading is not within specification, the gear must be replaced.
(5) Repeat procedure for all gears except the crankshaft gear.
d. Restore the engine to operating condition and check for normal operation.