Yanmar YM276 Service Manual page 657

Hydraulic system Tests and Diagnosis
270-20-9
SAFETY VALVE PRESSURE TEST
1. Install special adapter ( A ) t o port at left side of cylinder case.
Port:
M18,
Pitch
1.5
m m
2. Connect pressure line o f hand pump (B) t o the special adapter
(A).
3. install a pressure gauge measuring 24.5 MPa (250 kg/cm2)
(3000 psi) full-scale t o the adapter.
4.
Raise hydraulic l i f t t o maximum position. Set the control
valve t o the neutral position. Close stop valve o n cylinder head.
5. Increase pressure in cylinder w i t h the hand pump u n t i l the
safety relief valve operates to relieve o i l pressure.
A
-
Spcial AdmtEr
B -
From
Hand
Pump
C
-
P-re Gauge
SAFETY VALVE SPECIFICATIONS
Pressure
. . .
. .
16.7-18.6
M P a
1170-190
kglcrn' )
12417-2702
psi)
6. I f the reading deviates from the specification, adjust with
shims, page 70-1 5-7.
T w o shim thicknesses are available:
0.0078
in.
10.2
mml
0.0170
in.10.5
mml
A
CAUTION: Never raise pressure setting above 18.6 MPa
(190 kg/cm2
1
(2702
psi). Too high a suing defeats the
Purpose
of
the safeiy valve leading t o phton damage and/or
personal injury.