
87
CHAPTER 7. POWER STEERING SYSTEM
INSPECTION
Normally the operation of the solenoid valve should be checked on the machine, but as for wear of each
part or oil leaks it should be removed from the machine and checked according to the standards men-
tioned below.
• INSPECTION CONDITIONS
a. Working oil:
Equivalent to ISO VG-55
(Contamination degree is NASI12 or lower and solid material of larger than
0.1 mm should not be included.)
b. Oil temperature:
50
±
3
°
C
c. Oil flow:
As mentioned below
d. Working voltage:
DC 10.2V (Rated 12V, Maximum 14.4V)
• INSPECTION ITEMS AND CRITERIA
Items
Inspection
Criterion
1. Preparatory operation
With no load at port N1, N2 and C and both sole-
noid valves turned off, flush the valves by supplying
oil through port P.
(Flow at port P: 12 litres/min.)
2. Operating inspection
With a test cylinder connected to port C, confirm that
The valves should work
the test cylinder works properly by switching on and
properly without hitching,
off the solenoid valves a and b.
hunting or abnormal noise.
3. Measurement of
With all ports opened, solenoid valves at neutral and
7 kgf/cm
2
or lower
pressure loss
by supplying oil through port P, measure port P pres-
sure.
(Flow at port P: 12 litres/min.)
4. Pressure measurement 1
With port C opened and solenoid valve b turned on,
42
±
5 kgf/cm
2
by supplying oil through port P, measure port P pres-
sure.
(Flow at port P: 5 litres/min.)
5. Pressure measurement 2
With the manual push-pin depressed to the stroke end,
30
±
5 kgf/cm
2
measure port C pressure when oil is supplied through
port C.
(Flow at port C: 5 litres/min.)
(Flow at port P: None with solenoid valve turned off)
6. Measurement of oil leak
With the solenoid valves at neutral, measure leak while 3 cc/min. or less
applying load to port C.
(Load at port C: 100 kgf/cm
2
)
7. Push-pin operation
With the test cylinder connected to port C and load
The push-pin should work
applied, make sure that the cylinder works when the
securely to release load.
push-pin is depressed.
(Flow at port P: None with solenoid valve turned off)
(Load at port C: 50 kgf/cm
2
)
8. Inspection of appearance
Throughout all inspections there should be no abnormal
There should be no abnor-
noise, overheating, leakage, or malfunction.
mality.
Note: Inspection criteria may differ in accordance with the specifications of a product, make-up of test circuits.
For your reference: Conversion formula of SI units Pressure IMPa = 10.197 kgf/cm
2
Summary of Contents for SCM49
Page 1: ...S E R V I C E M A N U A L I S E K I L A W N M O W E R S LAWN MOWERS MOWER DECKS SCM48 SCM54 ...
Page 7: ...7 CHAPTER 1 INTRODUCTION 3 EXTERIOR VIEW AND DIMENSIONS 1935 mm 1965 mm 1100 mm 1265 mm ...
Page 36: ...36 SERVICE MANUAL FOR SGR19 SGR17 Fig 3 55 III 3 CYLINDER BLOCK 1 EXPLODED VIEWS ...