Daedong DSC48, Workshop Manual

Page: 235 / 290

Apr. 2007
6
-21
DSC48
2.4 HST TROUBLESHOOTING LIST
[Malfunction] [Check]
Insufficient
Low
Defective
Defective pump or motor
Low
Excessive
pressure
OK
OK
The combine is not
driven. Input shaft rotation
[Cause]
Defective delivery
system from engine
Insufficient oil supplied
Oil leakage
Clogged strainer
High viscosity
Defective suction pipe
Low temperature
Defective charge pipe
Clogged filter
Incorrect set pressure
Air in system
Defective low pressure
relief valve
Defective HST inner
part
Defective HST inner
part
Defective delivery
system between
transmission and axle
Incorrect operation
due to dust and chip
Foreign materials
entered
Seized valve plate and
piston
[Action]
Service delivery
system
Replenish oil
Check and correct
leaked part
Clean strainer
Change oil
Service suction pipe
Warm up engine
Service charge pipe
Replace filter
Replace high
pressure relief valve
Tighten suction hose
and plug
Check oil for
specification and
change to specified oil
Clean seats, replace
valve
Defective HST inner
part
Defective HST inner
part
Service delivery
system
Clean or replace low
pressure relief valve,
neutral valve and high
pressure relief valve
Clean or replace high
pressure relief valve
Replace HST
Input shaft rotation
High pressure relief
valves (forward and
reverse driving)
Charge pump output
pressure
No rotation
Charge pump inlet
pressure
Shift lever vibration, hydraulic load, excessive noise
and malfunction
Noise and vibration
occur during driving.
Only either forward or
rearward driving is
possible.
Combine cannot be
sped up, turned around
nor driven on a slope.
Pressure of low pressure
side of main circuit
Set pressure of high
pressure relief valve
Check with load applied
Low pressure relief
valve, neutral valve, high
pressure relief valve
Low