Can anybody tell me what this is, it has something to do with the cooling system. It is broke and bypassed now. Any kind of name/part number. thanks.

 

That is the heater control valve. It is a generic part that can be had at most auto parts stores. They typically cost about 14 bucks. it has a vacuum line at the top to switch the hot water to the heater core, or bypass it as needed.

 

Thanks Danno.