Hey anyone who can help. I have a 150XR2 mercury that overheats all the time and it seems I see that a lot. I am in the process of changing the poppet valvue and noticed that mine looks like half a poppet valvue. I saw how to put one on on-line and there was a smaller side to it that had a water line to it. I do not have this and the hole is plugged and no place for exsisting bolts to fit even if it were there. Is that something that changed with motor? I don't see how it works with no water line going to the valvue. HELP.