I willl never work on his jag again..........What a PITA to work on. Got it running it overheated, something went snap and engine shut off. I did a compression check next day, number 3 cylinder only had 55PSI, all the others had 130-135. I thought we burned a valve or something soooooooooo. It took me 7 hours to do the compression check and get all the chit off that side of the engine, JUST to get to the head, next day took 3 hours just to get the head off. After all that it wasn't the head, My nest guess it the timing chain broke and slipped a cog.
Just looking at it from what I can see, it looks fine. So next move, pull the front of the engine off. It APPEARS to me, that these v-12's are to be replaced rather then worked on hahahah. Amazing how hard it is just to get at bolts and nuts on the head. I had to make 2 tools and buy on, just to get at the fasteners.