20
Y
N
Moist electrode of spark plug
Dry electrode of spark plug
Check whether there is oil
spillover in the carburetor
Drop a little gasoline into the cylinder for trial startup
1.
Check whether the float
needle valve and the valve
seat are firmly combined
2.
Check whether the
conical surface of float
needle valve is abrasive as
stepped.
3.
Check whether the
carburetor float is broken
4.
Check whether the
carburetor float is too low
Check whether air
filter is blocked
Flameout shortly
after startup
Continue to work
after startup
The carburetor is blocked
inside or the float is too
high
Startup device of
carburetor (startup &
enrichment system)
is at fault
Remove spark
plug and check it
1.
Check leakage on outer
connections of the
engine.
2.
Check whether the piston
ring is seized in the
groove or whether it has
enough elasticity.
3.
Check abrasion of the
piston ring and the
cylinder.
1.
Check whether the
air vent in fuel tank
cover is blocked.
2.
Check whether the
fuel filter and the
fuel switch are
blocked.
3.
Check whether the
fuel switch works
normally.
4.
Check whether the
oil hole of the
carburetor is
blocked.
5.
Check whether the
carburetor float is
too high.
