TR4/4A Rocker Shaft Lubrication, and Issue with Push Rods

[KVH]

I just re-installed the rocker shaft and adjusted the tappets. I'm now worrying (how unusual) that I didn't check the oil hole from the cylinder head to be sure no debris is blocking the tiny galley. My manual says that oil flows up thru the block, then thru the cylinder head, and along that shaft.

My first question is whether I need to pull the rocker off again to check that galley. Is it really there and is it ever an issue that something gets in there and causes the oil to be blocked?

Second, isn't this process of turning the engine and cam to adjust the tappets somewhat in conflict with the advice that the tappets must be coated with zinc in a rebuild? Isn't the zinc rubbed off by the process of rotating the engine and then cranking it for start-up and first test?

Third, all of my pushrods have small flat spots on the bottom of the ball that fits into the tappet. They all look machined, not like it's due to wear. To clarify, the rods look fine, as do the upper cups, but the shiny ball end at the bottom of each of the 8 pushrods has a flat spot about 1/8 inch in diameter--at the very bottom of the ball. My extra push rod from Moss (ten years ago) has no such flat spot. Are some made that way, or do I have even wear that just looks a part of the design?

 

[TR3driver]

That's the route the oil takes, and it is possible for the passage to be blocked with sludge. The oil is at very low pressure and moves very slowly, so it's not good at clearing the passage. However, if you didn't find a lot of sludge elsewhere, it's probably fine. The path through the head is actually 3 intersecting holes; there is a plug on the LR corner that blocks one end of the horizontal leg.

Because of the way the oil flow to the rockers is controlled, it can take several minutes for the passage to fill and oil to start oozing from the holes in the rockers. So don't panic if you don't see oil right away.

In theory, the ZDDP forms an atomic bond with the steel, that only gets rubbed away if the oil layer fails. Then it reforms on the next cam revolution. Obviously you can't see the layer left on the steel, but it is what does the actual protection. So it shouldn't matter if the paste gets rubbed away.

The spot on the pushrods sounds normal to me, an artifact of the original machining process. The tip doesn't carry the load anyway, so it shouldn't matter.