Engine - Stihl SR 430 Manual

3.5

Engine

Always check and, if necessary,
repair the following parts before
looking for faults on the engine:
- Air filter
- Fuel system
- Carburetor
- Ignition system
Condition
Engine does not start easily, stalls
at idle speed, but operates normally
at full throttle
Engine does not deliver full power
or runs erratically
Engine overheating
SR 430, SR 450
Cause
Oil seals in crankcase damaged
Engine leaking or
damaged (cracks)
Seal on engine pan leaking
Muffler / spark arresting screen
carbonized
Air filter dirty
Tank vent faulty
Fuel suction hose kinked or torn
Piston rings worn
Insufficient cylinder cooling. Air
outlets on blower housing blocked
or cooling fins on cylinder very dirty
Remedy
Replace the oil seals
Seal or replace the engine
Re-seal the engine pan
Clean the muffler (inlet and
exhaust), replace spark arresting
screen, replace muffler if necessary
Replace air filter
Check the tank vent and replace if
necessary.
Fit new hose or position it free from
kinks
Fit new piston rings
Thoroughly clean all cooling air
openings and the cylinder fins
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