Inspection And Maintenance - Robin DY23-2D Service Manual

6-3-4 FUEL PASSAGE
From the plunger pump fuel is sent
through the high pressure
pipe 1 to the
fuel passage 2. Then, a t t h e nozzle body
3, it is pressurized up till 195 kg/c m' and
i t lifts up the
needle valve 4
for 0.18 mm,
and is injected into the combustion
chamber via the jet hole 5.
An excess fuel which lubricated the inside
of the nozzle and nozzle holder returns
to the fuel tank via the needle valve-,
nozzle spring 6 -overflow pipe 7 + - f u e l
tank. (See Fig. 7 1
.>
a
7
3
4
5
FIG. 71
6- 3- 5 INSPECTION AND MAINTENANCE
Fuel injecting condition of the nozzle and the valve opening pressure are quite influential
to the engine operation, insufficient output, increase of noise and exhaust smoke. Use of
improper fuel or contaminated fuel is one of the main causes of the nozzle trouble.
Therefore, exert good care for using good fuel. As the nozzle is assembled from very
precisely finished parts, utmost care and attention must
be paid when inspecting and
checking.
( 1
)
INSPECTION
After cleaning nozzle holder outside, inspect
in the following steps
:
a) Visual inspection
Whether or not injection hole is
damaged, or clogged with carbon.
Whether or not injection hole is clogged
with dust and carbon.
b) Checking by nozzle tester
Fit the nozzle assy to the nozzle tester.
When removing the nozzle
~ ~ Q P V I
the
engine
or
fitting, it to tester, be sure
t o .keep t h e nozzle free o f dust.
FIG. 72
Move the lever of the nozzle tester up
and down for
2-3
times and
suck the
air inside the nozzle.
Newer bring your face near the injected
fuel mist from the nozzle. Also keep
a w a y
your hands from the mist.
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