Stihl MS 200 Service Manual page 17

Condition
Engine speed drops quickly under
load – low power
16
Cause
Air filter dirty
Throttle shutter not opened fully
Tank vent faulty
Fuel pickup body dirty
Fuel strainer dirty
Leak in fuel hose between tank and
fuel pump
Setting of high speed screw H too
rich
Main jet bores or ports blocked
Pump diaphragm damaged or
fatigued
Impulse hose damaged, kinked or
not pushed onto stub below handle
housing
Ignition timing wrong, flywheel out
of adjustment, key in flywheel is
missing or has sheared off
Remedy
Clean air filter or replace if
necessary
Check throttle cable and rod
Replace tank vent
Install new pickup body
Clean fuel strainer in carburetor,
replace if necessary
Seal connections or install new fuel
hose
Check basic carburetor setting,
correct if necessary
Clean the carburetor
Fit new pump diaphragm
Fit impulse hose correctly or
replace if necessary
Fit key if necessary and secure
flywheel properly or install new
flywheel
MS 200, MS 200 T