
TM 9-1829A, April 1944
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2021-07-07
Chapter 6: Stewart warner speedometers and tachometers
Section I: Speedometers with cup-type magnets
Types 570, 579, 580, 581, 587, 589, 590, 679
28. Description
a.
This type Stewart-Warner speedometer (fig. 50) can be readily identified (internally) by the cup-type magnet
and the shape of the main frame. For complete description, operation and test procedure, refer to paragraphs
2 and 4.
Figure 50: Stewart-Warner speedometer with cup-type magnet disassembled
29. Disassembly
a.
Remove bezel and case:
(1)
Crimped bezel:
Pry up bezel at crimped points (with screwdriver) and remove bezel, gaskets, retainer,
and glass (or glass dial). (Some instruments of this type do not have a bezel or glass.) If necessary,
remove reset knob. Remove two case screws at back and lift out mechanism.
(2)
Rolled bezel:
Pry bezel loose (with screwdriver) at two points about 1 inch apart. Use cutting pliers and
tear out this section of bezel (fig. 51). Then pull bezel off (fig. 52) and remove other parts (par. a (1)
above).