Hey yall! The hubs and I are putting a D15B7 engine back together and transforming our civic into a dirt track racecar. In the midst of trying to hook all the necessary hoses back up I found a nipple behind the block next to the thermostat housing that spews out antifreeze when I try to fill the radiator. I cant figure out where it needs to be hooked to or if I can just put a cap on it. Here I have attached a picture.

 

That nipple is a part of the FITV/IACV coolant line passages.