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Section 21: Starting and Adjusting the Evolution Engine
If your engine starts from the above procedure, but won’t
reliably continue to run with the glow driver removed,
follow the steps above right.
Low-Speed Needle Adjustment
High-Speed Needle Adjustment
STeP 1: HIGH-SPeeD NeeDle ADjuSTMeNT
With the engine running, advance the throttle to full
throttle while a helper securely holds your airplane.
Carefully pinch and release the fuel line to temporarily
restrict the fuel flow.
Caution
: Do not reach over the propeller
while the engine is running.
Correct
: If the high-speed needle adjustment is correct,
the engine will increase rpm slightly (about 300 rpm) and
then die.
Too Rich
: If the engine increases a lot (1,000 rpm or
greater), the high-speed needle is too rich and must be
leaned or turned clockwise.
Too lean
: If the engine doesn’t increase rpm and simply
dies, the high-speed needle is lean and must be richened
or turned counterclockwise.
STeP 2: lOW-SPeeD NeeDle ADjuSTMeNT
The low-speed or idle needle valve, included with the
SetRight™ assembly, is preadjusted at the factory for best
performance. It may be necessary to fine-tune the low-
speed adjustment using the following procedure:
Step 1
Start the engine and let it warm up, prior to attempting any
adjustments. Make sure that the high-speed adjustment
process is complete before attempting to adjust the low-
speed needle valve.
Step 2
Close the throttle slowly. You will adjust the low-speed
needle setting by rotating the SetRight adjustment bar
clockwise to lean the engine and counterclockwise to
richen the engine.
Caution
: Do not attempt to adjust the low-
speed needle valve while the engine is running.
Step 3
The fuel mixture should be adjusted as follows: The fuel
mixture is too rich if, when opening the throttle rapidly,
the engine emits smoke and "stutters" or "stumbles."
Correct this by rotating the SetRight adjustment bar
clockwise in small increments. Continue this process until
the engine transitions smoothly from low rpm idle to high
rpm without hesitation upon opening the throttle rapidly.
Step 4
The fuel mixture may be too lean if the engine stops at the
lowest idle position or it stops when the throttle is rapidly
opened from the idle position. Correct this by rotating
the SetRight adjustment bar counterclockwise in small
increments until the engine transitions smoothly without
hesitation upon opening the throttle rapidly from idle.
The needle valves come preset from the factory. Extreme
conditions may require some minor adjustments. Note
that the needle adjustment range is limited, preventing
adjustment beyond the practical range.
