Converter Stall Test - TM-10-3930-243-340179

valve correspond exactly with those of the

( 3 ) Shift the transmission controls to high

range and forward.

operator's control. This adjustment is made in a

m a n n e r similar to the adjustment of the range

(4) Increase the engine speed to full throttle.

s e l e c t o r linkage ((1)above).

Converter out pressure should be 25 psi minimum.

(3) Inching control linkage, The

inching

NOTE

control valve is linked to a manual control valve,

Do not allow converter out temperature to exceed

expressly for inching. This valve is the transmission

250 F. Do not maintain full stall condition longer

than 30 seconds.

disconnect control valve. The transmission

disconnect control valve is located under driver's

(5) Use a tachometer and record the engine

floor board. For removal and installation, refer to

speed attain at full throttle operation.

TM 10-3930-243-12. The linkage must be adjusted

(6) The only reading derived from the stall test

t o insure full application and full release. The

is engine speed. The difference between established

inching control valve has a total linear movement of

normal speed and actual speed recorded is

2 . 0 2 inches from full retract (released) to full

significant only if it exceeds 150 rpm.

extension (applied).

3-40. Transmission Main Oil Pressure

(4) Output disconnect linkage. There are two

R e g u l a t i n g Valve

points of adjustment for the rear output disconnect

a. General. The main pressure regulating valve is

o n the transmission. The shifter shaft must be-

located on lower side of transmission secured to the

adjusted first, and then the linkage. Put the shifter

torque converter housing and supplies pressure to

shaft in (rearward) until the engaged detent seats.

the control valve.

A d j u s t the shifter shaft by rotating it until the

b. Removal. Refer to figure 3-96, step 4, and

center of the linkage connection hole is 0.610 to

remove transmission main oil pressure regulating

0.650 inch from the front surface of the transfer

valve,

c a s e . When the shifter shaft is pulled outward

c. Disassembly. Refer to figure 3-99 and

(rearward), the disconnect detent should seat when

disassemble transmission main oil pressure

the center of the shaft hole is approximately 23/8

regulating valve in numerical sequence.

inches from the transfer case surface. Adjust the

d. Cleaning and Inspection,

linkage so that the engaged and disconnect

(1) Clean all parts.

p o s i t i o n s of the operator's control correspond

(2) Clean oil passages by working a piece of

exactly with the detent positions of the shaft.

wire back and forth through passages and flush

3-39. Converter Stall Test

with cleaning solvent,

a. General. The converter stall test is a test of the

(3) Inspect bores for wear, grooves, scratches,

e n g i n e and transmission as a unit, wherein the

and dirt. Remove scratches and burs with crocus

transmission output is stalled while the engine is

cloth .

operated at full throttle. This test will indicate, by

(4) Clean and inspect gasket area. Replace a

the speed which the engine reaches, whether the

defective part.

engine a n d transmission a r e p e r f o r m i n g

e. Reassembly. Refer to figure 3-99 and

satisfactory under full load. A lower or higher speed

r e a s s e m b l e the transmission main oil pressure

than that established as normal are indications of

regulating valve.

either engine or transmission malfunction.

NOTE

b. Procedures.

The main oil pressure regulating valve may be ad-

(1) The test is made while the engine and

justed by adding or removing shims. Each shim will

transmission are installed. The vehicle wheels must

raise or lower pressure approximately 10 psi.

b e blocked securely to prevent movement. The

f. Installation. Refer to figure 3-97, step 55, and

b r a k e s should be applied except on those in-

reinstall transmission main oil pressure regulating

stallations which include a clutch cutoff valve.

valve.

(2) Start the engine and allow the transmission

to warm up to normal operating temperature

(180 to 200 F.).

3-141