
TM 9-1829A, April 1944
66/100
2021-07-07
Place speed cup and hair spring assembly inside field plate and install rear jewel bracket (two screws). Using
adjuster (T-178705), replace front jewel and adjust (fig. 96) to about 0.003 inch end play in pointer staff.
Insert end of hair spring in slot in hair spring regulator with end of spring protruding through slot about
1
/
8
inch.
Figure 96: Adjusting front jewel, using special tool (T-178705)
Using long-nosed pliers, squeeze pin tightly in position (fig. 97) with small end of pin pointing in the opposite
direction to which the end of hair spring is pointing.
Figure 97: Replacing hair spring pin
Using adjuster (T-51742), turn hair spring collet on staff (fig. 72) until speed cup stop rests against rear jewel
bracket and so that hair spring tends to pull speed cup in same direction as loose end of hair spring points.