TM 5-3805-260-24
TROUBLESHOOTING
Use this as a reference for the location and
correction of problems in the power train. When more
checking is necessary, use the 5P6225, 7S8875 or
8M2736 Hydraulic Test Box.
Always make visual checks first. Then check the
operation of the machine and go on to check with the
instruments.
VISUAL CHECKS
I. Check the oil level in the transmission.
2. Check all oil lines, hoses and connections for
leaks and damage. Look for oil on the ground
under the machine.
3. Move the selector handle to all REVERSE and all
FORWARD positions. The detents must be felt
in all positions.
4. Let the oil out of the filter housing. Remove and
check the filter element for loose particles. Also,
check the magentic strainer.
a. Bronze-colored particles give an indication of
clutch failure.
b. Shiny steel particles give the indication of a
clutch failure.
c. Rubber particles give an indication of a seal
failure or hose failure.
d. Aluminum particles give an indication of a
torque converter failure. If you find metal or
rubber particles, all components of the
transmission hydraulic system must be
washed clean. Do not use parts , with
damage. Use new parts.
CHECKS DURING OPERATION.
With the engine running, move the selector lever to
all speed positions. The detents must be felt in all
positions.
Operate the machine in each direction and in all
speeds. Make note of all noises that are not normal and
find their sources. If the operation is not correct, make
reference to the CHECK LIST DURING OPERATION for
"problems, " "probable causes, " and "recommended
action."
CHECK LIST DURING OPERATION
Transmission
PROBLEM
PROBABLE CAUSE
RECOMMENDED CORRECTIVE ACTION
Transmission does not operate in any speed or does
not engage (slips) in all speeds.
1. Low oil pressure.
a. Low oil level.
b. Control linkages loose or adjustment not
correct.
c. Failure of the oil pump or the pump drive.
d. Air leaks on inlet side of pump.
e. Leakage inside the transmission.
f. Adjustment of the modulation relief valve not
correct, or valve does not close.
g. Load piston or differential and safety valve
will not close.
1. Check oil level, adjust as needed.
2. Check control linkage for proper
adjustment.
3. Repair or replace oil pump/pump drive.
4. Repair or replace pump.
5. Repair as necessary to stop leakage.
6. Check modulation relief valve for proper
adjustment. If valve does not close,
repair or replace as necessary.
7. Repair or replace load piston/differential
and safety valve.
2.Mechanical failure in transmission.
a. Repair or replace parts as necessary.
3. Failure of the torque converter.
a. Repair or replace as necessary.
4. Failure of the differential or the final drive
planetaries.
a. Repair or replace the differential/final drive
planetaries.
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