Adjustments - TM-9-2520-254-340115

full

Engine speed at

throttle

(At closed throttle a downshift from third converter

downshift speed point is lower than 1,560 rpm, it is

to first converter occurs at 600 to 800 rpm engine

an indication that the valve is either sticking in its

speed.)

bore in an open position or that the inhibitor valve

NOTE

spring is faulty.

To convert engine speed readings, for the

NOTE

M113A1 family of vehicles, to trans-

To convert engine speed readings, for the

mission input speed, multiply engine

M113A1 family of vehicles, to trans-

speed by 1.286.

mission input speed, multiply engine

e. Lockup Shift Points. During full-throttle

speed by 1.286.

operation "at detent, " the lockup clutch should

5-63. Adjustments

engage when front governor (G1) pressure reaches

a. Manual Selector Linkage. Proper adjustment

44 psi.

of the manual selector linkage is important for

NOTE

proper vehicle performance. Refer to end item

All tests in d and e above are based on

organizational manual for procedures.

proper adjustment of the throttle valve

b. Throttle Linkage Underscored. There are

(TV) linkage.

two adjustments which must be made for throttle

f. Inhibitor Functional Check, 3-2 Downshift.

linkage. One is internal and must be made before

(1) Disconnect transmission output from

the oil pan is installed. The other is external and is

vehicle. drive line.

made after instilling the transmission in the

(2) Disconnect throttle valve linkage, and

vehicle. The internal adjustment concerns ad-

rotate throttle valve lever on transmission coun-

justment and locking of the headless screw in the

terclockwise until it reaches its internal stop.

throttle valve retainer at the rear of control valve

(3) Place manual selector control in 1-3

assembly (fig. 5-146).

position, and accelerate engine to 2,000 rpm.

NOTE

(4) Shift to 1-2 position, and slowly decrease

This adjustment is necessary only when a

engine speed. The 3-2 automatic downshift should

replacement control valve assembly (3, fig.

occur at 1,560 to 1,830 rpm engine speed.

5-82) or valve body (42, fig. 5-82) is in-

(5) If the 3-2 automatic downshift occurs at a

stalled. The adjustment, if required, is

speed higher than 1,830 rpm, it is an indication

made as follows:

that the high-to-intermediate inhibitor valve is

(1) On original control valve assembly,

sticking in its bore and not opening. If the

measure distance between rear of throttle valve

downshift speed point is lower than 1,560 rpm, it is

(depressed until it bottoms) and front of throttle

an indication that the valve is either sticking in its

valve stop screw. Record this dimension (fig. 5-

bore in an open position or that the inhibitor valve

146).

spring is faulty.

(2) On new control valve assembly, adjust

g. Inhibitor Functional Check, 2-1 Downshift.

stop screw until distance between rear of depressed

(1) Perform steps (1) and (2) as directed in f

throttle valve and front of stop screw corresponds

above.

exactly with measurement made in (1) above.

(2) place manual selector control in the 1-2

(3) Lock stop screw by crimping threaded

position, and accelerate engine to 2,000 rpm.

portion of retainer against flat side of stop screw

(3) Shift to l-position, and slowly decrease

(fig. 5-146).

engine speed. The 2-1 automatic downshift should

(4) The external adjustment concerns the

occur at 1,560 to 1,790 rpm engine speed.

linkage connecting the accelerator pedal, engine

(4) If the 2-1 automatic downshift occurs at a

fuel control, and transmission throttle lever. This

epeed higher than 1,790 rpm, it is an indication

adjustment is extremely important because it

that the intermediate-to-low inhibitor valve is

matches the transmission function to the engine

sticking in its bore and not opening. If the

5-65