Picked up this XJ a couple years ago with the engine knocking with only 136,000 miles. pulled and tore it down, found #3 wrist pin loose. There was also and inch of gunk on the head, somebody didnt know how to change the oil. Took it to the machine shop and had it punched 20 over and the head cleaned and checked. I put it together and re installed it. Still have issues tho.