Big fan in the engine bay

Hey guys, could you please tell me about the big fan that is usually in the engine bay of aircooled beetle's

Why do some cars not have one? if they are being driven in traffic or slowly in residentail areas is it better to have one?

Also how do you know when the engine is over heating? thanks 😀

All beetles have fans on the engines as standard. The ones you may be refering to are the Porsche style fan housings which have a big visible fan. Standard fans are inside the big round housing that sits near the firewall. The pulley that drives the generator (the cylinder thing that sticks into the housing) also drives the fan.

Some pics would help explain but I don't have any on hand.

This car has the Porsche style fan housing:

http://forums.aussieveedubbers.com/viewthread.php?tid=38650&page=1

This is standard style (with twin carbs):

ahhhh 😀😀😀 thanks for the snappy reply, yes the pics help explain, the car does have the big black housing in back so i guess its all good :bounce never had much experience with air cooled engines except lawnmowers hahah thanks!