Yanmar 3TNV Series Service Manual page 141

8. Turbochager
(b) Measuring instruments and devices
Dial gage
Manometer
Pressure regulating valve
Pressure reducing valve
Pressure gage
(c) Check method
1) Set the manometer control pressure (Pc) applied to the waste gate actuator to 0 and set the dial
gage to the zero point.
2) Gradually open the pressure regulating valve and measure the Pc value when the actuator rod is
operated by 2 mm.
3) For the hysteresis, let the rod move to 3 mm first. The gradually close the pressure regulating
valve, measure the pressure when the rod is moved to 2mm and obtain the difference from the
pressure measured in b. above.
4) Precautions
Set the dial gage on the extension line of the actuator rod.
The piping and joints shall completely be free from leak.
Fix the turbocharger and dial gage securely.
If an electric manometer is used, it shall have sufficient precision.
Even when an electric manometer is used, use of a mercury column type manometer in
combination is recommended for calibration and daily check.
The speed for increasing/decreasing Pc by means of the pressure regulating valve shall be very
slow near the measuring point. If the mm position is exceeded, restart from the beginning.
Do not apply over 0.49 MPa (5 kgf/cm
(2) Waste gate actuator leak test
Apply 0.12 Mpa (1.2kgf/cm
pressure then is 0.11 Mpa (1.1kgf/cm
Capable of measuring 0 to 10 mm (A flat head type is recommendable.)
Mercury column or electrical type (capable of measuring 0 to 1500 mmHg)
Allowing gradual adjustment in a range between 0 and 2 kgf/cm
Used for suppressing the air supply pressure at 5 kgf/cm
Bourdon tube pressure gage (0 to 10 kgf/cm
2
) to the actuator.
2
) to the actuator and hold the state for minute. The actuator is good if the
2
) or above.
2
(0.98 Mpa))
126
2
(0.196 Mpa)
2
(0.49 Mpa) or less.