DRIVE TRAIN SECTION 7
Page 21
DRESSTA TD-25M EXTRA
SERVICE DIAGNOSIS
3. Shift the drive train control lever into neutral and move the drive train neutral lock lever to ON
position. Place the engine speed control lever in the low idle position and stop the engine.
4. If the readings are within these ranges with the oil at operating temperature, proceed with
STEERING SYSTEM OIL PRESSURE CHECK, Par. 13 in this Section.
5. If the readings are not within these ranges with the oil at operating temperature, refer to the
following diagnostic chart.
Transmission and Torque Converter Diagnostic Chart
PROBLEM PROBABLE CAUSE
1. Low main oil pressure a. Low oil level in rear frame. Refer to OPERATOR’S MANUAL.
b. Clogged suction oil filter. Refer to OPERATOR’S MANUAL.
c. Leaking pump inlet lines.
d. Fatigued or broken main spool springs in regulator valve.
e. Incorrect number of shims at main spool in pressure regulator
valve. Each shim changes the pressure by approximately
35 [kPa]. DO NOT use more than a total three shims.
f.
Safety check ball or spring in pressure regulator valve
malfunction.
g. Steering system leaking. Perform STEERING SYSTEM
SUPPLY PRESSURE TEST described in this Section.
h. Defective rear section of pump.
2. High main oil pressure a. Main regulator spool stuck.
b. Incorrect priority valve adjustment after repairing or
replacement.
3. Low torque converter oil
pressure
a. Low main oil pressure. Refer to problem 1 above.
b. Clogged suction oil filter. Refer to OPERATOR’S MANUAL.
c. Leaking pump inlet lines.
d. Stuck converter spool in pressure regulator valve.
e.
Fatigued or broken converter spool spring in pressure
regulator valve.
f.
Incorrect number of shims at converter spool in pressure
regulator valve. Each shim changes the pressure by
approximately 25 [kPa]. DO NOT use more than a total three
shims.
g. Internal leak in converter. Check sleeve hub and output shaft
seal rings.
h. Defective rear section of pump.
4. High torque converter oil
pressure.
a. Restricted or blocked oil passage or line.
b. Restricted oil cooler.
5. Low transmission lubrication
oil pressure.
a. Low torque converter oil pressure. Refer to problem 3 above.
b.
Fatigued or broken lubrication spool spring in pressure
regulator valve.
c. Stuck lubrication spool in pressure regulator valve.
d. Incorrect number of shims at lube spool in pressure regulator
valve. Each shim changes the pressure by approximately
7 [kPa]. DO NOT use more than a total three shims.
To Next Page
Loading...