![background image](http://html1.mh-extra.com/html/stihl/fs-40/fs-40_service-manual_1378633015.webp)
14
Series 4144 Components FC, FS, KM
4.5
Engine
Always check and, if necessary,
repair the following parts before
looking for faults on the engine:
- Air filter
- Fuel system
- Carburetor
- Ignition system
Condition
Cause
Remedy
Engine does not start easily, stalls
at idle speed, but operates normally
at full throttle
Oil seals in crankcase damaged
Replace the oil seals
Crankcase leaking or damaged
(cracks)
Seal or replace the crankcase
Engine does not deliver full power
or runs erratically
Piston ring worn or broken
Fit new piston ring
Muffler / spark arresting screen
carbonized
Clean the muffler (inlet and
exhaust), replace spark arresting
screen, replace muffler if necessary
Air filter dirty
Replace air filter
Fuel hose kinked or torn
Fit new hose or position it free from
kinks
Engine overheating
Insufficient cylinder cooling. Air
inlets blocked or cooling fins on
cylinder very dirty
Thoroughly clean all cooling air
openings and the cylinder fins
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 ...