Hi guys

I need some guidense.

Please bare over with me as I am from oversea, and might not use the terms, words etc as you might do.

Short story long.. My motor has been rebuild a few years back. A lot of things could have been done different that I know.
It has driven around 3000-3500 miles since then. I have been inspecting cam and pushrods maybe 2000-2500 miles ago because of a enoying tik/tapping noise I had since day one after the rebuild.
Listening to advice I should give it some time to “break in” but it never dissapeared.
I tried all sort of engine type.. diesel engine oil, Classic oil, thinner modern oil etc etc just to see if it made any change. All in all no change, at least the tik/tapping noise has always been there in some way.
When doing this inspection about 2000 miles ago, I found that my lifters was fully compressed with valves in closed position, I read that hydraulic flat tappets needed a preload of in between .020 - .060” . They did not have that.. I could not compress the piston in the lifter any more than it was.
After dissasembling everything and inspection as good as I could, this goes for cam, valvetrain and lifter removed amd taken apart, cleaned and tested the spring, I put in some shorter pushrods that gave me .040” of preload(I used a adjustable pushrod to find the right length), I put everything back together. Everything was more or less the same... the tik was a bit different. I was struggleing with manifold leaks at the time, but is has been solved, but the tik/tap was still there.

Now the actual problem... Once again I felt like I needed to have a closer look, simce the tapping kind of increased, dissapeared amd came back.

I removed the valvecovers. At the drivers side I found the white snot which Imassume is cause by bad ventilation since there is no breather in this valvecover. Then I got sad as I found a grey creamy paste of metal in the rear of the head by the oil drain hole.. without discussion it was worst in the drivers side. The paste was tested with a magnet.. it was metal for sure!
I have replaced the engine oil Very often, and have not found any glitter in the oil surface, I even had a finger up the drain hole in the pan a few times without getting sludge on my finger.
I cleaned up the grey metal paste, and with the valvecovers removed I started the motor, and found I would say was hat everything was working as intended. At least it looks like it.
One thing I did notice before and after the start up was cylinder 3 was different than the others... the spring for the exhaust valve can be moved a little bit under the rocker arm, and the pushrod for the intakevalve can be moved up and down a tiny bit. All other rocker/valve/spring are firm... pushrods can be turn with fingers, but are not looses.

Using a long screwdriver as a listening device I can hear the mechanical function on all the rockers... I can not hear any difference, from one to another.

Should I be worried, about the creamy metal paste, or the “loose” spring / pushrod (I know I have to do something about it).

What should be my next move ?

Could the lifters have been damaged from being so compressed at the begining ?

Could the lifter valve pump-up function be bad without me actually being able to feel or test it ?

The motor starts and drives without any issues beside the above.. it does not burn any oil, does not use any water. Its just that enoying tik tik tik/tap tap tap noise !!

I apologizes for the size of the pictures.. I did not succed when I tried to make them smaller.