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13
Series 4144 Components FC, FS, KM
Condition
Cause
Remedy
Engine speed drops quickly under
load – low power
Air filter dirty
Clean air filter or replace if
necessary
Throttle shutter not opened fully
Check throttle cable and cable
adjustment and readjust if
necessary
Tank vent faulty
Replace tank vent
Fuel pickup body dirty
Install new pickup body
Fuel strainer dirty
Clean fuel strainer in carburetor,
replace if necessary
Leak in fuel hose between tank and
fuel pump
Install new hose
Setting of high speed screw
H
too
rich
Check basic carburetor setting,
correct if necessary
Main jet bores or ports blocked
Clean the carburetor
Pump diaphragm damaged or
fatigued
Fit new pump diaphragm
Ignition timing wrong, flywheel out
of adjustment, key on crankshaft
has sheared off
Locate flywheel properly or install
new flywheel
Summary of Contents for FS 40
Page 1: ...STIH STIHL Series 4144 Components FC FS KM 2008 02 FS 40 FS 50 FS 56 FC 56 KM 56 ...
Page 79: ...78 Series 4144 Components FC FS KM ...
Page 80: ...79 Series 4144 Components FC FS KM ...
Page 81: ...80 Series 4144 Components FC FS KM ...
Page 82: ...englisch english 0455 545 0123 M7 E8 FST Printed in Germany ...