What is the threaded passage way in front of the water passage on an Imco lower for? My -2 lower had the port plugged but I recently swapped for a standard length Imco and it does not have the plug installed in it.

When bolted to an Imco SC upper case there is a water hose that connects to it for cooling the top cap, I believe.

Dick

Thank you sir. After looking it lines up with the speedo port on my upper which isn't used so I plugged it back up.