Yamaha DT501988 Owner's Manual page 57

If overheating is detected, perform the fol-
lowing checks:
Engine overheating
Wait until the temp.
guage indicates tower
than 50"C (122°F) line
{see page 5-5)
Check the coolant level
in the reservoir tank
and/or radiator.
OK
Restart the engine. If the
engine overheats again,
ask a Yamaha dealer to
inspect and repair.
U-043
Check the cooling
system for leakage.
No leakage. Leakage
Add coolant• Ask a Yamaha
dealer to inspect
and repair.
NOTE: _ _ _ _ _ _ _ _ _ _ _
If it is difficult to get the recommended coo-
lant, tap water can be temporarily used,
provided that it is changed to the recom-
mended coolant as soon as possible.
7.9
2. Changing the coolant
a. Remove the radiator cover and radiator
cap.
b. Place a container under the engine.
c. Remove the drain bolts.
1. Drain bolts 2. Hosing cover 3. Cylinder
d. Drain the coolant completely, and thor-
oughly flush the cooling system with
clean tap water.
e. Retighten the drain bolts. If the gasket
is damaged, replace it.