I ran into a problem with the valley drain hole in the back of the engine and have some questions. First this is about the 6.5NA that is in my HMMWV. I tried to post this on the 6.2/6/5 tech, but for some reason I was not able to. No problem for me if it gets moved. I thought the hole was plugged at first, which caused water to lay around and corrode my IP and caused it to leak. Trying to clear the hole, I realized it was blocked off for some reason and there was a small core plug installed where the tube would have exited on the drivers side of the back of the block. I used a small punch to force the core plug into the bell housing area and tried to clear the hole going through the back of the valley. the punch went up against something solid and would not break through. Has this ever happened to anyone else? I do not want to pull the transmission to fix this. does anyone see any problem with me trying to drill through the hole to let any future water or anything else drain out in the bell housing area.