Stihl 029, 039 - Page 13

STIHL 029, 039 13
Condition Cause Remedy
Engine stalls at idle speed Idle jet bores or ports Clean jet bores and ports
blocked with compressed air
Idle jet "too rich" Screw down low speed adjusting
screw slightly
(see Carburetor Adjustment)
Setting of idle speed Set idle speed adjusting
adjusting screw incorrect screw correctly
- throttle shutter completely
closed
Small plastic plate in valve Clean or renew valve jet
jet does not close
Engine speed drops quickly under Air filter plugged Clean air filter
load - low power
Tank vent faulty Clean or replace tank vent
if necessary
Leak in fuel line between tank Seal or renew connections
and fuel pump and fuel line
Pump diaphragm damaged or Fit new pump diaphragm
fatigued
Main jet bores or ports Clean bores and ports
blocked
Fuel pickup body dirty Clean pickup body, fit new
filter
Fuel strainers dirty Clean fuel strainers
See also 2.2