Stihl MS 192 T Manual page 15

Problem
Engine will not idle, idle speed too
high
Engine stops when idling
Engine speed drops quickly under
load – low power
14
Cause
Throttle shutter opened too wide by
idle speed screw LA
Oil seals / crankcase leaking
Idle jet bores or ports blocked
Idle jet too rich or
too lean
Setting of idle speed screw
incorrect – throttle shutter
completely closed
Air filter dirty
Throttle shutter not opened fully
Tank vent faulty
Fuel pick-up body dirty
Fuel strainer dirty
Leak in fuel line 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 or kinked
Remedy
Reset idle speed screw LA
correctly
Seal or replace oil seals /
crankcase
Clean the carburetor
Set low speed screw L correctly
Reset idle speed screw LA
correctly
Clean the air filter
Check linkage
Clean tank vent or replace if
necessary
Clean the pick-up body or replace if
necessary
Clean fuel strainer in carburetor or
replace if necessary
Seal connections or install a new
fuel line
Turn the high speed screw H
clockwise (leaner) – max. up to the
stop.
Clean the carburetor
Fit new pump diaphragm
Fit new impulse hose
MS 192 T