Stihl SR 430 Manual page 14

Condition
Engine will not idle, idle speed too
high
Engine stops while idling
SR 430, SR 450
Cause
Throttle shutter opened too wide by
idle speed screw (LA)
Oil seals/engine leaking
Throttle shutter stiff or torsion
spring on throttle shaft fatigued or
broken
Idle jet bores
or ports blocked
Setting of low speed screw (L) too
rich or too lean
Setting of idle speed screw (LA )
incorrect – throttle shutter
completely closed
Remedy
Reset idle speed screw (LA)
correctly
Seal or replace oil seals/engine
Free off throttle shaft or install new
carburetor
Clean the carburetor
Reset low speed screw (L)
correctly
Reset idle speed screw (LA)
correctly
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