Stihl FS 50 Service Manual

13Series 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

Stihl FS 50 Specifications

General

Engine Displacement	27.2 cc
Power Output	0.8 kW
Engine Type	2-stroke
Shaft Type	Straight
Starter System	Recoil
Overall Length	147 cm
Vibration Level	4.5 m/s²