TM 9-2350-247-20-2
ADJUST THROTTLE VALVE (TV) MODULATOR (M548A3) -- Continued
0204 00
TESTING
FIELD OPERATIONAL TEST
NOTE
Use judgment in evaluating speedometer readings by considering variables that may affect the
speedometer.
A cable-driven speedometer can be affected by temperature and moisture, amount of bend in
the cable, age, number of miles on the carrier, amount of lubricant used, and manufacturing
tolerance error of 5 percent. All of these possibilities can result in speedometer lag (a reading
slower than the actual speed during acceleration).
The angle in which the driver looks at the speedometer can cause a 1-2 mph (2-3 km/h) error/
difference. The height of an individual, seat height, or angle could account for inconsistency in
speedometer readings. The higher the driver's vantage point, the more the driver tends to read
below the actual speed.
If the transmission shifts smoothly and reaches top speed (30-39 mph (48-63 km/h) without
lagging during wide open throttle tests, consider the adjustment complete even if the
speedometer reading is somewhat outside the limits shown in the following steps.
1.
Operate carrier (see your -10). Drive carrier on straight, level terrain with shift lever in the 1-4 position. Accelerate
carrier with accelerator pedal fully pressed (wide open throttle). Verify that the following transmission shifts occur at
speeds shown: Upshift 1 to 2
7 mph (11 km/h) min Upshift 2 to 3
18 mph (29 km/h) max
NOTE
If shifts are within ranges, adjustment is complete. If not, do Step 2 and Step 3.
2.
If upshift 1 to 2 is below 7 mph (11 km/h), do ADJUSTMENT Step 11 again.
3.
If upshift 2 to 3 is above 18 mph (29 km/h), do ADJUSTMENT Step 12 again.
NOTE
Do Step 4 only if the minimum/maximum shift points in Step 1 have not been obtained.
4.
If more adjustment is needed, reposition throttle valve modulator lever (6) as follows:
a.
Loosen nut (7), nut (8), and nut (9).
b.
Adjust throttle valve modulator lever (6) away from modulator bracket (10) if upshift 1 to 2 is below 7 mph
(11 km/h).
c.
Adjust throttle valve modulator lever (6) toward modulator bracket (10) if upshift 2 to 3 is above 18 mph (29 km/h).
d.
Tighten nut (7), nut (8), and nut (9).
5.
Repeat Steps 1 - 4 until shift ranges are met.
