this might sound dumb but i have a leak on the back of my motor found this line that runs to the head any buddy know what this line is called i think its part cooling system.anyhelp would be appreciated.

 

Put up a picture.

 

I'm guessing that since you think its part of cooling that you can tell what kind of fluid it is?

 

That's the return line for the heater core. Those hoses are a bitch to change and only cost like $15 if it's just the hose. There is also a rubber hose under the lower intake that it could be from as well unless you have already pin pointed the spot. Anyways, the back of the driverside head goes to the heater core.