Im working on my new S83P getting it painted for the farm and going through the systems. The coolant is leaking out of a fitting at the top of the engine. It looks like this fitting was attached to a hose at one point but corroded and now it's leaking at the base. The fitting itself is not corroded and can be moved with a wrench. Can anyone tell me what this is? What it is for? Was there a hose connected? I've uploaded a photo. Thank you for any help!