tryin to break in new engine, ruff idle

I know what your sayin, the lifters can bleed down. but what I discovered, upon close examination of the lifters and tryin to understand exactly how they work... the spring pressure in the lifter is at least enough to keep the pushrod up in contact with the rocker, even if it has bled down and wouldn't really give much lift until the engine is run and oil pressure builds again.

Even though I can press some of the rockers down (the ones that have bled down), by hand, they spring back up and keep the pushrod touching the rocker. But the #1 and #3 exhaust valves pushrods don't even touch the rockers (about 1/8" gap), even considering the lifter is fully extended by its little spring pressure.

So basically, I push the rocker down 1/8", it hits the pushrod, then I can push it (or bounce it up and down) another 1/4" or so due to the spring in the lifter.

None of the other lifters that have bled down have that 1/8" slack/gap... just the freeplay allowed by the spring in the lifter. Does that make any sense? Thanks again!