Yanmar 3JH4E Service Manual page 108

2. Inspection and adjustment
When removing the spacer, never draw the
spacer by force.
Wax pellet will be damaged by the reaction
shock.
Remove the spacer and return the C.S.D. lever
carefully, while turning the C.S.D. lever by
using a screw driver or steel bar.
8) Remove the dial gage, and screw driver or
steel bar. Install the plug and gasket.
Tightening torque of the plug: 20-25N•m.
(2) Check the injection spray condition of a
fuel nozzle
Wear protective glasses when testing injection
from the fuel injection nozzle. Never approach
the injection nozzle portion with a hand. The oil
jetting out from the nozzle is at a high pressure
to cause loss of sight or injury if coming into
careless contact with it.
1) Injection pressure measurement
Standard MPa (kgf/cm
21.1-22.1
(215-225)
[NOTICE]
As for the opening pressure of the brand-new
fuel nozzle, about 0.5 MPa (5 kgf/cm) declines
by the engine operation for about 5 hours
because of the initial wear-out of a spring etc.
Therefore, adjust 0.5 MPa (5 kgf/cm) higher
than the standard value of the above table
when adjusting a new fuel nozzle of a spare
part.
Remove carbon deposit at the nozzle hole
thoroughly before measurement.
a) Connect the fuel injection valve to the high
pressure pipe of the nozzle tester.
b) Operate the nozzle tester lever slowly and
read the pressure at the moment when the
fuel injection from the nozzle starts.
c) If the measured injection pressure is lower
than the standard level, replace the
pressure adjusting shim with a thicker one.
Thickness of pressure adjusting shims
0.13, 0.15, 0.18, 0.4, 0.5, 0.8
2
)
mm
The injection pressure is increased by approx. 1.9 MPa (19 kgf / cm
when the adjusting shim thickness is increased by 0.1 mm.
Injection pressure adjustment
88
010627-00X
2
),