Stihl FS 240 Service Manual page 16

Problem
Power loss during acceleration, all
versions
... Versions with M-Tronic
Engine will not idle, idle speed too
high, versions without M-Tronic
... All versions
... Versions with M-Tronic
Engine stops when idling, versions
without M-Tronic
... All versions
... Versions with M-Tronic
FS 240 C, FS 260 C, FS 360 C, FS 410 C, FS 460 C-M
Cause
Seal or spring of accelerator pump
worn or damaged
Parts in carburetor or M-Tronic
wiring harness defective
Throttle shutter opened too wide by
idle speed screw LA
Oil seals / crankcase leaking
Throttle shutter does not close
Parts in carburetor or M-Tronic
wiring harness defective
Idle speed screw "too rich" or
"too lean"
Idle speed screw LA
setting incorrect – throttle shutter
completely closed
Idle jet bores
or ports blocked
Tank vent faulty
Leak in fuel line between tank and
carburetor
Parts in carburetor or M-Tronic
wiring harness defective
Remedy
Replace carburetor
Carry out M-Tronic diagnosis, if
necessary, replace carburetor or
M-Tronic wiring harness
Set idle speed screw LA correctly
Seal oil seals / crankcase, replace if
necessary
Replace carburetor
Carry out M-Tronic diagnosis, if
necessary, replace carburetor or
M-Tronic wiring harness
Correct setting of low speed
screw L
Set idle speed screw LA correctly
Clean the carburetor
Replace tank vent
Seal connections or replace line
Carry out M-Tronic diagnosis, if
necessary, replace carburetor or
M-Tronic wiring harness
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