Unwanted present post oil change

Time to spend some time on maintenance, and what I thought would be another simple oil & oil filter change.

Ran for a few minutes to warm things up, side drain open, nice black but probably still servicable oil. As usual 5 litres out, 5 litres in - so despite the drips under the car I'm not losing much/any in day to day running.

No swarf in the oil coming out - good sign.

The front drain plug gives access to the oil pickup filter. I thought it may have been leaking/weeping around the bottom of the plug so for the first time since the build intending to take this out, inspect and clean up.

Left is the oil pickup filter/grille and its drain plug, right the main oil drain plug. I'm replacing the blank original aluminium washers, top, with seal insert Dowty washers, bottom. (Stainless new washers on the ali sump may not have been the best idea - may change it)

Spare part - loose valve collet

This, what appears to be a valve collet, was sitting inside the oil pickup filter.

I have no idea how long its been there. To get to that location it has managed to get to the sump and be sucked back up by the oil take up then lodged in the grille.

It looks in clean undamaged as-new condition, hopefully that means it made the journey through the engine via the oil galleries and not by forging its own path through the cylinders or block, its plainly a very hard component, but surely would show some witness if it went through the engine?

No sign of issues when the engine was running, for obvious reasons I'm not running it again though.

Nothing out of place looking at the top of the engine, cams, followers etc, so some planning required before moving to the next step.

Update - removed the cams/lifters etc and inspected all the valves - nothing amiss, the collet is a spare part.