I have a 1968 bettle

Chek your oil level, it may be low or the oil pum may be failing.

The engine has a large fan that helps cool the engine. It is attached to the rear of the Generator.

Make sure that the belt tension for the Generator is OK (the fan / generator will slip if the belt is too loose).

The fan is "keyed" to the generator shaft. If the key is broken, then the fan can slip on the shaft. Again, check if
the fan is tight on the shaft (engine off, reach around the fan shroud and try to spin the fan with your hand to see
if it slips).

Check for debris in the fan blades. A rag / towel or leaves can clog the fan blades causing less air to be drawn
through the fan for cooling.

The engine should have a thermostat that controls the opening & closing of fins at the base of the fan housing. Check
to see if the thermostat "expands" when the engine gets warm.

Lastly, check your ignition timing. Timing that is too far advanced will cause the engine to run hot.

Thomas