Stihl 4144 Series - STIHL Powerhead Engine Service; Engine Leakage Test

12 Series 4144 Components FC, FS, KM
Condition Cause Remedy
Engine will not idle, idle speed too
high
Throttle shutter opened too wide by
idle speed screw LA
Reset idle speed screw LA
correctly
Oil seals/crankcase leaking Seal or replace oil seals/crankcase
Engine stalls at idle speed Idle jet bores
or ports blocked
Clean the carburetor
Setting of low speed screw too rich
or
too lean
Reset low speed screw L correctly
Setting of idle speed screw LA
incorrect – throttle shutter
completely closed
Reset idle speed screw LA
correctly
Tank vent faulty Replace tank vent
Leak in fuel hose between tank and
fuel pump
Install new hose