Stihl SR 430 Manual page 15

Condition
Engine speed drops quickly under
load – low power
14
Cause
Air filter dirty
Throttle shutter not opened fully
Tank vent faulty
Fuel pickup body dirty
Fuel strainer dirty
Leak in the fuel suction hose
Setting of high speed screw (H) too
rich
Main jet bores or ports blocked
Pump diaphragm damaged or
fatigued
Remedy
Clean air filter or replace if
necessary
Check throttle cable
Replace tank vent
Install new fuel pickup body
Clean fuel strainer in carburetor,
replace if necessary
Install new fuel suction hose
Check basic carburetor setting,
correct if necessary
Clean or replace the carburetor
Fit new pump diaphragm
SR 430, SR 450