I consider the 60K mark or the first service thereafter the point at which you endoscope or pull the front end to inspect it and change it IF you have other work pending that will pull the car off of the road anyway. 80K is when I like to and reccomend changing it.

When I see them at 100K Km I advise that you are on borrowed time.

Most often ailure usually results in a new set of pushrods, rockers and rocker bolts.
If you get unlucky then its headgasket and a couple of valves.
If you're really unlucky then you will need all of the above plus anything up to a new piston (or a set if you're not a scrimpy rebuilder) and head.
If you crossed paths with a black cat while walking under a ladder at the same time smashing your hand mirror as your horseshoe amulet hung upside down Then you buy a new engine.

It could be worse along with your leak going from they do that to but not that much your phone call could have started with, Mate do you want to know what happened when we tried to start it up to move it for you or do you just wan to spend the $3k Fixing it?

__________________
Dave

"In a Landrover the other vehicle is your crumple zone."

Fozzy, 2.25D SIII Ex DCA Ute
The midlife crisis car
Some D1

For spelling call Rogets, for mechanicing call me.