Mazda 2008 RX-8 Owner's Manual page 261

If you find a leak or other damage, or if
coolant is still leaking:
Stop the engine and call an Authorized
Mazda Dealer.
If you find no problems, the engine is
cool, and no leaks are obvious:
Carefully add coolant as required (page
8-13).
CAUTION
If the engine continues to overheat or
frequently overheats, have the
cooling system inspected. The engine
could be seriously damaged unless
repairs are made. Consult an
Authorized Mazda Dealer.
In Case of an Emergency
Overheating
7-17