Troubleshooting - KTM 450 SX-F Owner's Manual

TROUBLESHOOTING

9 T ROUBLESHOOTING
Faults
The engine cannot be cranked (electric
starter).
Engine turns but does not start.
Engine has no idle.
Possible cause
Battery discharged
Fuse blown
Low external temperature
Operating error
Motorcycle was out of use for a long time
and there is old fuel in the float chamber
Fuel feed interrupted
Engine flooded
Spark plug oily or wet
Electrode distance (plug gap) of spark
plug too wide
Spark plug connector or spark plug
defective
Short-circuit cable in wiring harness
chafed, short-circuit button defective
Socket connector of CDI control device,
pulse generator or ignition coil oxidized.
Water in carburetor or jets blocked
Idling jet blocked
Adjusting screws on carburetor distorted
Spark plug defective
Measure
–
Recharge the battery. (
–
Check the cause of discharging.
–
Remove the fuse. ( 52)
–
Replace the fuse. ( 52)
–
Use the battery supplied in the acces-
sory package.
450 SX-F, 505 SX-F
4Ah battery (YTX5L-BS) (
–
Conduct check ( 14).
–
Empty the carburetor float chamber.
( 63)
–
Check tank vent.
–
Clean fuel tap.
–
Clean carburetor.
–
Clean and dry spark plug or replace if
necessary.
–
Clean and dry spark plug or replace if
necessary.
–
Adjust plug gap.
Rules
spark plug electrode gap
0.7 mm (0.03 in)
Warning
Risk of injury The ignition
system is under high voltage.
–
Do not touch parts of the
ignition system.
work on the ignition system
carried out in an authorized
KTM workshop.
–
Remove spark plug, connect ignition
cable, hold spark plug to ground (bare
metal area on engine), and try to start
the engine.
Rules
You should see a strong spark on the
spark plug.
–
If there is no spark, change the spark
plug.
–
If there is still no spark, remove the
spark plug cap from the ignition cable,
hold it at the specified distance from
the ground contact, and try to start the
engine.
Rules
5 mm (0.2 in)
–
If you now have a spark, replace the
spark plug connector.
–
If there is no spark, have the ignition
system checked.
–
Check wiring harness. (visual check)
–
Check electrical system.
–
Clean socket connector and treat it with
contact spray.
–
Clean carburetor.
–
Clean carburetor.
–
Have the carburetor adjusted.
–
Change spark plug.
67
51)
76)
Have