KTM 400 EXC Owner's Manual page 53

TROUBLESHOOTING
TROUBLE
Engine does not rev high
Engine will not reach full power Fuel supply partially interrupted or carbu-
Engine stops or splutters in
carburetor
52
Engine gets too hot
High oil consumption
All switched on lamps blown
out
Horn, flasher lights and
E-starter do not work
The battery is discharged
»
CAUSE
Carburetor fuel level too high because float
needle valve is dirty or worn out
Loose carburetor jets
Electronic ignition timing faulty
retor dirty
Float leaks
Air filter very dirty
Exhaust system is not tight, deformed, or
the silencer does not contain enough glass-
fiber yarn
Valve gap too small
Loss of compression because hand decom-
pressor has no play
Electronic ignition timing faulty
Insuffient fuel
Engine takes air out of control
Insufficient cooling liquid
Not enough air stream
Cooling system has not been bled
Radiators very dirty
Foam formation in cooling system
Bent cooling hose
Thermostat defective
Blown fan fuse (XC Desert)
Defect thermoswitch (XC Desert)
Fan defective (XC Desert)
Hose of engine ventilation is bent
Engine oil level too high
Motor oil too thin (viscosity)
Capacitor or voltage regulator faulty
Blown fuse in the starter relay
The battery isn't charged by the generator
because
REMEDY
Dismount carburetor and check if worn out
Tighten jets
Have ignition system checked
Clean and check fuel system as well as carburetor
Replace the float
Clean or replace air filter
Check if exhaust is damaged, replace glasfiber yarn in
exhaust silencer
Adjust valve gap
Check setting of the hand decompression cable
Have ignition system checked
Clean and check fuel system and carburettor
Check rubber sleeve and carburetor for tight fit
Refill cooling liquid (see maintenace work), check cooling
system for leaks
Drive on briskly (electric fan can be retrofitted)
Bleed cooling system
Clean radiators with water jet
Replace cooling liquid, use antifreeze liquid with brand name
Shorten or replace cooling hose
Dismount and check thermostat (opening temperature
70°C, (158°F) or replace it
Replace fuse and check if fan operates properly (see
below)
Contact a KTM dealer
Check if fan operates properly. To do this, start the
engine, then bypass the connections to the thermoswitch
(bottom right radiator), contact a KTM dealer
Dislocate i.e. replace non-buckling vetilation hose
Check engine oil level and, if necessary, correct it
Use thicker engine oil; see chapter "Engine oil"
Dismount seat and fuel tank and check connections, have
capacitor and voltage regulator checked
Dismount left side paneling and filter box cover, replace
fuse
Remove seat and fuel tank and check voltage regulator con-
nections; voltage regulator and generator should be checked
by a KTM dealer.