KEEWAY F-ACT EVO - Failure Diagonosis (Continued); Failure diagonosis procedure of unstable engine idle speed

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Failure diagonosis procedure of unstable engine idle speed
Bad idle speed of engine
Engine’s idle speed too high
Engine has no idle speed
Engine’s idle speed unstable
Check the cylinder compression pressure
Pull the air throttle of carburetor by
hand and check if it is closed
completely
Use ignition timing light to test
whether engine ignition is timing
cylinder compression
pressure insufficient
cylinder compression
pressure normal
1. Check if there is gas
leaking in external
connections of the engine
2. Check if the piston
ring sticks in ring groove
or insufficient elasticity
3. Check the wearability
of piston ring and
cylinder
Readjust the idle speed
of carburetor
Check if
the idling
jet is too
large
Check if the
wire rope of
accelerator
control cable is
flexible in
cable cover and
if the air
throttle spring
is too weak
1. Check if the CDI
ignition apparatus fails
2. Check if the magneto
flywheel and trigger
winding loosen
Engine has idle
speed after
adjustment
Engine still has
no idle speed
after adjustment
The carburetor air
adjusting screw
or air throttle
adjusting screw is
adjusted
improperly
Check if the idling jet of
carburetor, idling oil
channel and air flue
block
Wash and clear out
Check if carburetor float is too high
Adjust the carburetor
float height to standard
value
1. Check if there is crackle in the carburetor
insulator
2. Check if the retaining nut of carburetor
loosens
3. Check if the negative pressure pipe of fuel
cock breaks
4. Check if the leaf valve leaks
Adjust the gap of
electrodes
Check the mixture
ratio of the
combustible gas
mixture
Check if
the gap
between
spark plug
electrodes
is too
small