KTM 250 EXC 2004 - Manual (Page 39)

ENGLISH
38
Cooling system
The water pump in the engine circulates the cooling liquid. However, the
cooling liquid can only circulate properly if the cooling circuit contains no air
bubbles.
Bleeding of the cooling system is therefore required
a) after adding more than 0.25 l cooling liquid and
b) after refilling the entire cooling system.
(see Bleeding the cooling system).
Some models are equipped with a thermostat
1 so that the engine reaches
its operating temperature more quickly. When the engine is cold, the liquid
coolant circulates in the cylinder and the cylinder head. As soon as the
cooling liquid has reached a temperature of approximately 55°C, the ther-
mostat opens and the cooling liquid is also pumped through the two alumi-
num radiators.
The cooling liquid is cooled by the air stream. This means that the cooling
effect decreases with the traveling speed. Dirty radiators additionally reduce
the cooling effect.
ƽ WARNING ƽ
– I F POSSIBLE , ALWAYS CHECK LEVEL OF COOLING LIQUID WHEN ENGINE IS COLD . I F YOU
HAVE TO OPEN THE RADIATOR CAP 2 WHEN THE ENGINE IS HOT , USE A RAG TO COVER
THE CAP AND OPEN SLOWLY TO RELEASE PRESSURE . C AUTION - SCALDING HAZARD .
– D O NOT DETACH ANY RADIATOR HOSES WHILE THE ENGINE IS HOT . T HE ESCAPING
HOT COOLANT AND THE STEAM MAY CAUSE SERIOUS BURNS .
– I N CASE YOU GET BURNT , HOLD THE AFFECTED PART OF YOUR BODY UNDER RUNNING
COLD WATER RIGHT AWAY .
– C OOLANT IS TOXIC . K EEP THE COOLANT OUT OF THE REACH OF CHILDREN .
– I N CASE COOLANT IS INGESTED , CONSULT A DOCTOR IMMEDIATELY .
– I F COOLANT GETS INTO YOUR EYES , RINSE THEM OUT WITH WATER IMMEDIATELY
AND GO SEE A DOCTOR .
A mixture of 40% antifreeze liquid and 60% water is used as coolant.
However, the antifreeze protection must be at least -25° C (-13° F). This
mixture offers antifreeze protection but also good corrosion protection and
should therefore not be replaced by pure water.
! CAUTION !
F OR THE COOLING SYSTEM , USE ONLY WITH HIGH - GRADE ANTIFREEZE ( E . G . M OTOREX
A NTI - F REEZE ). U SING LOWER - GRADE ANTIFREEZE AGENTS CAN CAUSE CORROSION AND
COOLANT FOAMING .
Pressure induced by heating of the coolant in the system is controlled by a
valve in the radiator cap
2 ; a water temperature of up to 120° C (248° F) is
admissible without, having to expect any trouble.
Radiator cover for the cold season
To ensure that the engine reaches its operative temperature also at low
temperatures, the radiator cover
3 must be mounted.
For this purpose, detach the left radiator protection 4 and mount the cover
in front of the left radiator as illustrated.
Remount the radiator protection.
NOTE: The radiator shutter can be obtained
from your KTM dealer
Checking the coolant level
The coolant should be 10 mm (0.4 in) above the radiator fins when the
engine is cold (see diagram). In the event of the coolant being drained,
always fill and bleed the system.
ƽ WARNING ƽ
I F POSSIBLE , ALWAYS CHECK THE LEVEL OF COOLING LIQUID WHEN THE ENGINE IS COLD .
I F YOU HAVE TO OPEN THE RADIATOR CAP WHEN THE ENGINE IS HOT , USE A RAG TO
COVER THE CAP AND OPEN SLOWLY TO RELEASE PRESSURE .
! CAUTION !
T HE COOLING SYSTEM MUST BE BLED AFTER DRAINING THE COOLING LIQUID OR AFTER
ADDING MORE THAN 0.25 L (0.06 US GALLONS ) COOLING LIQUID .
4
3
when engine is cold
10 mm
1
2
4
3