Carburetor - Stihl SR 430 Manual

3.4

Carburetor

Condition
Carburetor floods
– engine stalls
Poor acceleration
12
Cause
Inlet needle not sealing
– Foreign matter between valve
seat and sealing cone or sealing
cone worn
Inlet control lever sticking on
spindle
Helical spring not located on nipple
of inlet control lever
Perforated disc on metering
diaphragm is deformed and
presses constantly against the inlet
control lever
Setting of low speed screw (L) too
lean
Setting of high speed screw (H) too
lean
Inlet needle sticking to valve seat
Diaphragm gasket leaking
Metering diaphragm damaged or
shrunk
Spacer flange damaged
Remedy
Remove and clean the inlet needle,
clean the carburetor
Clean the inlet control lever or
replace if necessary.
Remove the inlet control lever and
refit it correctly
Fit a new metering diaphragm
Check basic carburetor setting,
correct if necessary
Check basic carburetor setting,
correct if necessary
Remove inlet needle, clean and
refit
Fit new diaphragm gasket
Fit a new metering diaphragm
Install new spacer flange
SR 430, SR 450