TM 9-2320-266-34
that all bolts securing a particular part will be tightened to
b. Aluminum Thread Repair. Damaged or worn threads
the same torque. Refer to figure 4-21.
in the aluminum transmission case and valve body can be
repaired by the use of Heli-CoiIs or their equivalent.
4-9. Draining and Refilling Transmission Fluid.
Essentially, this repair consists of drilling out the worn or
damaged threads, tapping the hole with a special Heli-Coil
a Place a drain container with a large opening under the
tap or equivalent. and installirg a Heli-Coil or equivalent in-
transmission oil pan.
sert into the tapped hole. This brings the hole back to its
b. Loosen the pan bolts and tap the pan at one corner to
original thread size. Refer to table 4-3 for details. Some
break it loose, allowing fluid to drain. Remove the oil pan.
thread drag may occur in screwing a bolt into the installed
Heli-Coil or equivalent insert. Therefore, a torque reading
c. Remove the access plate in front of the converter, and
remove the drain plug (figure 4-22). Allow the fluid to drain.
should be taken of the thread drag with an inch-pound
Install and tighten the converter drain plug and install the
torque wrench, and added to the specified bolt torque, so
access plate.
Figure 4-21. Heli-Coil or Equivalent Installation.
Table 4-3. Heli-Coil Chart
4-18
