I am the proud new owner of a 95 pathfinder XE with 180K on the clock. When I got it home I noticed that there was a coolant leak from the rear passenger side head above the exhaust. I removed the heat shield and couldn't determine where the leak was coming from so I assumed the head gasket was leaking. Pulled the head and found that the rearmost upper exhaust stud hole had been drilled out and retapped with a larger bolt. Seems like the PO drilled too deep, and hit the water jacket. Therefore, the water was leaking around the exhaust stud bolt and dripping on to the manifold. I can see the rusty stains from where this has been happening. Anyhow, anyone know if it's possible to weld up the hole, then retap it for the correct stud? If I knew this beforehand, I would have tried removing the oversize stud, then put some sealant or jb weld back around the stud and let it go. But since I already have the head off, might as well fix it right. I'm doing the timing belt and water pump as well. Should I do the oil pump too, what is the life span of the oil pump on these motors? Thanks for any input. RG