where do i get this??

just after a 3 hour drive home from easter week end i pulled up at a servo to re fuel and and little old woman came up and pointed out to me that my 300 was leaking green stuff as she put it all over the ground....i parked the car a popped the boonet and missing out of the radiator on my left hand side at the end is a screw of some kind iv never taken notice of it since iv only owned the zed for couple weeks now......i need this fixed rite away does any one know were to get one and why it would have lodged its self out.....the car sat bellow half temp the hole trip?? cheers and sorry i couldnt upload a pic

 

sounds like the bleed valve?

Oposite end of the rad from the cap?

 

yep that sounds about rite sorry for bad details

 

I wouldn't drive anywhere without that. The radiator fluid will just keep coming out. Then you'll cook your motor.

 

Yep, coolant needs to be under pressure to retard boiling.

 

And the stocko temp guage wont work without having water on it....