Husqvarna NUDA 900 R 2012 Workshop Manual page 25

NUDA 900 2012/2013 - NUDA 900 R 2012/2013
Trouble
Engine runs irregularly at idle
Engine runs irregularly at higher speed
Engine has no or insufficient performance
TROUBLESHOOTING
Possible causes
Excessive spark plug electrode gap
Valve clearance below specification
Intake socket not tight or leaking
Ignition unit defective, ignition timing in-
correct
Valves leaking
For other possible causes see also "Engine
starts over but does not start engine or
starts hard"
Fuel pressure too low
Leak air
Camshafts worn
For other possible causes see also "Engine
starts over but does not start engine or
starts hard"
Leak air, intake system leaking
Spark plugs not according to specifications
or defective
Valve clearance not according specifica-
tion
Valve timing incorrect
Ignition coil supplies insufficient ignition
voltage
Ignition unit defective, ignition timing in-
correct
Valves leaking
Clutch slipping
Fuel pressure too low
Air filter dirty
Exhaust system defective
Excessive Blow-by gases, Piston rings and/
or cylinder bore worn
Engine oil not according to specifications
C.3
Remedy
Exchange spark plug
Adjust valve clearance according to spe-
cification
Tighten intake socket or exchange if ne-
cessary
Check / replace crank position trigger and
ECU
Rework valve seats
Check fuel pressure sensor, fuel pump and
fuel supply
Check / replace intake socket
Check and replace if necessary
Check / replace intake socket
Replace spark plug
Adjust valve clearance according to spe-
cification
Adjust position of camshaft gears
Check / replace ignition coil
Check / replace crank position trigger and
ECU
Exchange valves, rework valve seats
See remedies "clutch is slipping".
Check fuel pressure sensor, fuel pump and
fuel supply
Exchange
Exchange
Exchange piston rings and/or cylinder
Exchange engine oil
Manuale d'officina Ed. 11-2011