Stihl BT 45 Manual page 11

Condition
Poor acceleration
Carburetor floods,
engine stalls
10
Cause
Idle jet too lean
Main jet too lean
Inlet control lever too low
(relative to correct installed
position)
Inlet needle sticking to valve seat
Connecting bore to atmosphere
blocked
Diaphragm gasket leaking
Metering diaphragm damaged or
shrunk
Inlet needle not sealing. Foreign
matter in valve seat or cone
damaged
Inlet control lever sticking on
spindle
Helical spring not located on nipple
of inlet control lever
Perforated disc on diaphragm is
deformed and presses constantly
against inlet control lever
Inlet control lever too low
(relative to correct installed
position)
Remedy
Back off the low speed screw
slightly
(see Adjusting the Carburetor)
Back off the high speed screw
slightly
(see Adjusting the Carburetor)
Replace the inlet control lever
Remove inlet needle, clean and
refit
Clean bore
Fit new diaphragm gasket
Fit new metering diaphragm
Remove and clean or replace inlet
needle, clean fuel tank, pickup
body and fuel line if necessary
Free off inlet control lever
Remove inlet control lever and refit
correctly
Fit new metering diaphragm
Fit new inlet control lever
BT 45