Hi all!
Recently been having some issues such as consistently losing coolant with no puddles, white smoke, milky oil, etc etc,
anyways the current hope is that its simply a blown head gasket and not a cracked block, (I own an 86 Xj6 which If my information is correct is a year in which they did not use the horizontal coolant passages in the block that are notorious for cracking)
anyways ive gotten around to disconnecting the exhaust and after looking behind th exhaust manifold I saw a part I was unfamiliar with.
any info on it or if it needs to be replaced would be great, ill attach a pic below.

(there are two other circular spots but with what looks like either very very tightly fitted plugs or just metal attached to the head itself inside)

 

Never mind...

 

"Lo Temp Void If Removed"

I'm wondering if that's one of those heat sensitive pellets installed by engine rebuilders. If the engine overheats the pellet pops-up (or something) and the rebuilder voids the engine warranty.

Cheers
DD

 

I believe you are correct! the head did indeed have some work done to it at one point, am not exactly sure to what extent but this seems to be something left in by a machinist.
appreciate the quick response and help!

 

Just a note to say that although the later slotted blocks didn't crack, head gasket failure is not uncommon at around the 80-90k mile mark. Even the later AJ6 engines could blow a head gasket at relatively low mileages.