Evolution 15cc, Руководство пользователя

Страница: 12 / 72

EN
12
Because of the small amount of fuel actually
needed for this engine, needle adjustments
need to be made in small increments. It may
take 5 seconds or more before you will notice
a running change in your engine after making
it. Be patient.
Use a tachometer, this is a very
important part of properly setting your high-
speed needle valve.
The procedure below is for ground setting the
needles prior to flight. The final adjustments
need to be made after noting the performance
in the air.
1. With engine started and warmed up, open
the throttle fully and note the rpm. Listen to
the engine.
a. If the engine occasionally mis-fires but
maintains a fairly constant rpm after 5
seconds, your engine is rich. Reduce the
throttle to idle and turn in (clockwise)
the high-speed needle 2 clicks. Repeat
this until the engine stops mis-firing.
b. If the engine does not mis-fire and the
rpm steadily decreases from the highest
rpm achieved when you opened the
throttle, it is lean. Reduce the throttle
to idle and open (counterclockwise)
the high-speed needle 2 clicks. Repeat
this until the engine maintains the rpm
achieved when the throttle is wide open
Your goal here is to achieve a good
transition between high and low speed,
and that the high-speed rpm will be
steady on the ground.
2. Fly your aircraft for the in-air testing.
a. During flight, if the engine seems to slow
down or sag when climbing, your engine
is running slightly lean. Land the
airplane and open the high-speed
needle valve 2 clicks and take-off again.
b. During flight, if you hear the engine mis-
firing occasionally in level flight, this is
an indication it is running too rich. Land
the airplane and close the high-speed
needle valve 2 clicks and take-off again.
c. Repeat the above process until your
engine performance is steady and
repeatable. This high-speed needle
setting should not change more than
+/– 1–2 clicks in the future when using
the same propeller. If it does, something
is wrong in the fuel delivery system and
should be investigated.
If you are using onboard telemetry and have
a temperature monitor on the head of your
engine, your readings should be between
200°F (93°C) and 300°F (149°C). If you see
consistent temperatures above 340°F (171°C)
you should land your airplane and add
baffling to your cowl in order to increase
cooling to the engine. See the Telemetry
section for information on the proper
positioning of your sensor.
High-Speed Needle Adjustment