Robin America DY30 Service Manual page 38

2) Maintenance
If the test results are found not good (poor injection and "after dripping"), carefully check and repair
in
the following
manner:
a) Disassemble the nozzle holder and nozzle, and wash
in clean light oil. When washng, use a wooden chip
(for instance, wooden chopstick is servicable.) for
peeling off the carbon adhered t o the nozzle.
b) After shing, pull out the needle halfway from
NEEDLE
the body of nozzle with your fingers and then let
it go. And check if the needle sinks by its own dead
BODY
weight.
c) If it does not sink, replace it in the form of a set.
d) Frinction surfaces of both the needle and nozzle
body are ultra precise finish.
So,
be sure t o keep
the parts free of dust.
e) If "after dripping" is found, it is poor contact be-
tween the needle valve and the seat. In such a case,
it is advisable to replace it in the
form of a set, nee- Fig. 66
dle valve and nozzle body. However, it is possible
to coat chrome oxide on the tapered surface of the needle and get a good contact. Wash very carefully after correc-
tion.
f )
Adjustment of the valve opening pressure of the nozzle spring in the nozzle holder
is unnecessary because it was al-
ready adjusted by the adjusting washer.
g) The spacer is an important part to set positions of the nozzle holder and the nozzle body. Pay attention to the posi-
tion of the pin.
h) When fitting the nozzle body to the nozzle holder, conform to the specified tightening toruqe,
viz.
[Tightening torque: 400
-
500
kg-cml
i) Recheck with the nozzle tester, if necessary.
-35
-