Thrush Aircraft S2R-R1340 Maintenance Manual page 98

Table 4-1: Engine Trouble Shooting Chart, Page 3 of 13
TROUBLE
Improper idling of
engine
(continued)
Engine runs rough
4-28
THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
PROBABLE CAUSE
Improper valve clearance
Sticking valves
Restriction in exhaust system
Low compression in one or more
cylinder
Loose spark plugs
Defective spark plugs or leads
Defective breaker points
Defective magneto
Dead cylinder
Faulty ignition switch
Pre-ignition and detonation
Fuel pressure too high
Fuel pressure too low
Leak in induction system
Fuel leak
Automatic mixture control valve
sticking
Faulty carburetor
REMEDY
Reset valve
Reset valve
Remove restriction
Replace cylinder. Refer
to Engine Manufacturer's
Manual
Tighten spark plugs
Replace spark plugs
Replace breaker points
Replace magneto
Check plugs, high-tension
leads, and valve clearances
Replace switch
Reset timing
Adjust fuel pump.
Check for clogged fuel
lines or strainers. Check
operation of boost and fuel
pump, and adjust if
necessary.
Replace gaskets; tighten to
correct torques
Check fuel line
connections
Replace mixture control
valve
Replace carburetor
Effective: 01/01/2008