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b)
Trip odometer (fig: 8):
The trip odometer is also driven by the “third gear”, through the trip
odometer drive gear, and another gear at the trip odometer. The trip odometer usually has four figure
wheels and is so constructed that as any one figure wheel finishes a complete revolution, it turns the
next figure wheel to the left
1
/
10
of a revolution. The figure wheel on the extreme right registers in
tenths of a mile. The trip odometer is usually equipped with a reset mechanism so that the mileage
on the trip odometer can be reset as desired.
Figure 8: Schematic view of a trip odometer
3. Identification
a.
Purpose:
Before starting the actual repair of a speedometer or tachometer, it is necessary to determine its
original manufacturer, so that the proper chapter of this manual may be referred to for instructions.
b.
Methods of identifying instrument manufacturer:
(1)
“AC” Company name: “AC Spark Plug, Flint, Michigan” stamped on rear of case (fig. 9). A part number,
by which service parts are determined, is always stenciled on the case. This number will look like this:
“1567101 B-206576” or new stamping as “1567470-6208454.” The first number is the “AC”
identification, and the second is the applicable ordnance number.
(2)
Auto-Lite: Part number or “Motometer G&E Division, La Crosse, Wisconsin, USA” stamped on rear of
case (fig. 10).
(3)
(3) King-Seeley: Letters “KS” preceding the part number of face dial and stamped in rear of case (fig.
11).
(4)
Stewart-Warner: Part number stamped on the back of the case (fig. 12), by the letters “SW” preceding
the part number of the face dial, or by the name “Stewart-Warner” on the face dial.
(5)
Waltham: Marking at bottom of face dial reading “Waltham, made in USA” (fig. 13).
Figure 9: Rear of AC speedometer
Figure 10: Rear of Auto-Lite Speedometer