Yamaha R25 Series Owner's Manual page 87

Periodic maintenance and adjustment
Engine overheating
WARNING
Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
Place a thick rag, like a towel, over the radiator cap, and then slowly rotate the cap counterclockwise to the
detent to allow any residual pressure to escape. When the hissing sound has stopped, press down on the cap
while turning it counterclockwise, and then remove the cap.
Wait until the
7
engine has cooled.
TIP
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Check the coolant level in the
reservoir and radiator.
There is
leakage.
The coolant level is low.
Check the cooling system
for leakage.
There is
no leakage.
Start the engine. If the engine overheats again, have a
The coolant level
Yamaha dealer check and repair the cooling system.
is OK.
7-42
EWAT1041
Have a Yamaha dealer check
and repair the cooling system.
Add coolant. (See TIP.)