Specifications

Power Train Testing and Adjusting 39
Check List during Operation
Problem: Engine starts with directional control
switch in FORWARD or REVERSE.
Probable cause:
1. Directional control switch is defective
Problem: Transmission shifts with parking brake
engaged.
Probable cause:
1. Parking brake switch is defective.
Problem: Transmission will not stay in gear when
shifted.
Probable cause:
1. Parking brake switch mounting is loose.
Problem: Transmission does not operate in either
direction or does not shift.
Probable cause:
1. Problems in the electrical circuit (directional con-
trol)
a. Open circuit between ignition switch and direc-
tional control switch.
b. Defective directional control switch.
c. Defective wiring harness between directional
control switch and transmission.
d. Shorted wiring harness for the solenoids.
2. Low oil pressure or no oil pressure caused by:
a. Iow oil, no oil or thick oil.
b. Inching control valve linkage loose, broken or
adjustment is not correct.
c. Inching valve reducing spool stuck open.
d. Failure of the oil pump or a defect in the oil
pump.
e. Main relief valve stuck open.
f. Restriction in the oil flow circuit such as dirty oil
screen.
g. Leakage inside the transmission.
Worn or broken metal seal rings on input
or reverse shaft.
Worn or broken seals around clutch piston.
Modulating valve assemblies stuck
Because of contaminated oil
3. External oil lines are not connected correctly.
4. Mechanical failure in the transmission.
Problem: Transmission operates only in
FORWARD.
Probable cause:
1. Forward clutch is locked up.
2. Reverse solenoid valve does not actuate.
3. Reverse clutch components have damage.
a. Leakage caused by worn or broken metal sea-
ling rings.
b. Leakage caused by worn or broken clutch piston.
c. Failure of shaft seal ring.
Problem: Transmission operates only in REVERSE.
Probable cause:
1. Reverse clutch is locked up.
2. Forward solenoid valve does not actuate.
3. Forward clutch components have damage.
a. Leakage caused by worn or broken metal
sealing rings
b. Leakage caused by worn or broken seal around
clutch piston.
c. Failure of shaft seal ring.
Problem: Transmission gets hot.
Probable cause:
1. Restriction in cooling circuit.
2. Oil level too high or too low.
3. Core of the oil cooler not completely open.
4. Low pump pressure - worn or damaged pump.
5. Converter one-way clutch worn and slipping.
6. Air mixed in the oil. Air leaks on the intake side of
the pump.