Replacing my valve cover gaskets. Seems there are noted problems with wearing rockers and what not. What should I be looking for when inspecting the valvetrain?

 

Burnt or worn surfaces on the rocker arms, pushrods.
Excessive carbon build up.
If it runs good, unless you want to spend money, I'de do the valve covers and call it good.

 

If you're concerned about anything internal, the best thing to replace would be the oil pump.
Cheap, and an easy job.

 

What will I see, is it Loose, shinny/dark or what? I don't have much experience with worn rockers or shafts.

 

Blueing, burnt discoloration, scoring, scratches.
Carbon built up around where pushrods fit into rocker.
You will have to unbolt rocker shafts to see, and they need torqued when you put them back.
They should not be loose.
Normal wear would be a small polished, smooth surface, not much bigger that the top of the valve.
At 120k miles, running good, without heating, ticking or rattling, I would think everything would be ok.
I just did an oil pump at 122k miles, main gear in mine was broken in 3 pieces. Engine would tick after thermostat opened, and I had ruled out slipped sleeve or head gaskets.
I also bought lifters, pushrods and rocker shafts too. As I was unsure if it was oil pump or a lifter ticking.
As cheap as Lucky8's prices are, I think it was worth doing. At least knowing that they should last the rest of the engine's life. And everything inside was clean and in good shape, other than oil pump. Someone had done head gaskets already.
So, all in what you want to spend, if anything, since yours sounds like it's good, other than leaking valve covers.

 

I have worked on many different vehicles over the years, but this is my first LR. Very easy to work on.
As far as common problems or failures, I can only pass along what I've read.
I have read that tips can break off of rockers. But you would definately hear and see that. I have also read that rocker shafts can crack. That may or may not be visible.
Even after removing the rocker arms. The rockers just slide on the shaft. Springs between them, and washers with cotter keys on each end is all that holds them, and the 4 bolts mounting the shaft to each head.
As said, I replaced shafts, pushrods, lifters, and oil pump.
Not knowing what I'de find when I opened it, upping the odds I'de have what I needed to fix it, and piece of mind that those parts shouldn't and hopefully cause no future problems.

 

Very odd. I've actually never heard of broken rockers on these engines, and goodness knows mine would be a prime target considering how I drive her.

Oil pump definitely needs to happen. I change mine ever 60k or every time I've got the front cover off. Personally I wouldn't go over 80k on any of these Rover V8s but I do it ag 60k because that's when all the fluids and everything get changed anyway, so they don't have to be changed twice.

 

They have been known to let go from time to time. Not a everyday occurence

 

Definitely good to know to keep an eye on. Guess ill keep that extra set of rockers kicking around if I haven't already gotten rid of them.

 

I had a rocker arm shaft break on my D1.