TM 9-1829A, April 1944
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2021-07-07
20. Disassembly
a.
Remove bezel and glass:
Cut bezel and remove bezel, glass, gaskets, and dial retainer.
b.
Remove case:
Remove mounting bracket and unscrew reset knob or flexible cable. Remove two case screws,
remove case, being careful not to lose main frame dust washer, and on SPK-type; be careful not to lose felt
washer on reset mechanism.
c.
Remove pointer:
Grasp pointer firmly at center, being careful not to bend it, twist slightly counterclockwise,
and pull to remove.
d.
Remove dial:
Remove dial screws, being careful not to mar dial, and lift off dial.
e.
Remove trip odometer reset bracket
(fig. 39): Remove two screws and lift off. Case can be placed on bench
in inverted position and used as a stand for main frame during disassembly.
Figure 39: SPK-type speedometer mechanism (dial removed)
f.
Remove odometer
(fig. 39): Remove total odometer spacer clip. Move bushing out of bearing slot, at same
time pulling odometer pinion carriers from front jewel bracket until they clear bracket. Repeat to remove trip
odometer.
g.
Remove hair spring
(fig. 39):
(1)
Place one nose of pliers against small end of locking pin and other nose against upper part of regulator,
gently tighten pliers to remove pin, then rotate speed cup until end of hair spring is free from regulator.
(2)
Remove hair spring with special puller (T-66296); slide lower plate of puller between hair spring hub
and jewel lock nut and tighten puller screw (fig. 26). It may be necessary to pry hair spring hub up slightly
(fig. 29) to make clearance for puller.
h.
Remove front jewel bracket
(figs. 33 and 39): With special screwdriver (T-178705) and wrench remove
lock nut, regulator, and jewel. Remove two bracket screws and lift off bracket.
i.
Remove third gear:
Remove third gear; do not lose any washers which may be at either end of gear.
j.
Remove speed cup and field plate
(fig. 40): Hold main frame in inverted position and straighten out
crimping at lower edge of field plate and lift off both speed cup and field plate.
Figure 40: Removing field plate and speed cup