Hitachi ZW 550-G, Technical Manual

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03-6
Measurement for Performance Check
Standard Measurement Values for Performance Check
H
ydr
aulic line
Relief valve setting
pressure
MPa (kgf/cm
2
) (psi)
Loading line main relief pressure (HI)
20.6 ± 0.5 (210 ± 5)
(2,986 ± 71)
Loading line overload relief pressure (LI)
23.5 ± 0.5 (240 ± 5)
(3,413 ± 71)
Run engine at lowest
possible speed while
setting
Steering line main relief pressure (HI)
20.6 ± 0.5 (210 ± 5)
(2,986 ± 71)
Steering line overload relief pressure (LI)
24.5
+1.0
0
(250
+10
0
)
(3,555
+142
0
)
Run engine at lowest
possible speed while
setting
Fan motor line relief pressure (HI)
(Reference values)
S/N 9001~9010
Low press.: 9.5 (97) (1,380)
High press.: 19.0 (194)
(2,760)
S/N 9011~
Low press.: 9.5 (97) (1,380)
High press.: 18.1 (185)
(2,625)
Pilot line reducing pressure (LI) 3.5 (36) (512)
Fan maximum revo-
lution
min
-1
(rpm)
S/N 9001~9010
Engine water temp. < 94ºC (200ºF) 1,120 Low press. 9.5 MPa
Engine water temp. > 94ºC (200ºF) 1,600
High press. 19.0
MPa
S/N 9011~
Engine water temp. < 80ºC (176ºF) 1,120 Low press. 9.5 MPa
Engine water temp. > 93ºC (200ºF) 1,600
High press. 18.1
MPa
Brake
Performance of ser-
vice brake
Shift lever position 2nd speed reverse
Slowly increase the engine
speed, and check that the
machine does not move at
the maximum engine speed.
Engine speed Maximum (HI)
Performance of park-
ing brake
Shift lever position 3rd speed reverse
↑
Before brake check,
be sure to discon-
nect the cable con-
nector of parking
brake solenoid valve.
Engine speed Maximum (HI)
Brake line setting
pressure
MPa (kgf/cm
2
) (psi)
Unloader valve
setting pressure
(LI)
Off (Cut-out)
11.8 ± 0.5 (120 ± 5)
(1,706 ± 71)
On (Cut-in)
6.9 ± 1.0 (70 ± 10)
(995 ± 142)
Low-pressure alarm switch setting pressure
(For brake accumulator circuit) 3.9 ± 0.3 (40 ± 3)
(569 ± 43)
Brake line reducing pressure 12.3 (125) (1,778)
Auto brake reducing pressure 3.5 (36) (512)
Accumulator charge
time (sec)
Engine speed (LI)
The time from the low-pressure
alarm is turned off till the unloading
valve cuts off pressure
16
Number of brake
pedal applications
Run engine 1 minute high idle, then stop the engine.
(Turn key switch “ON” with engine off.)
Step on the brake pedal and release, and check the num-
ber of times until the low-pressure alarm is turned on.
at least 11 times
Repeat stepping on
the brake pedal as
follows:
On: 5 seconds
Off: 5 seconds
Declutch engagement
(cm) (in) Engine: Maximum speed/ Inching pedal: Quick release
(Distance the loader rolls back before moving forward.)
15 (6) or less
1/5 slope
(approx. 11º),
unladen, 1st speed