Found these in the oil strainer. Magnified one and its the shape of an isosceles trapezoid. Size of a tooth pick tip. Magnetic. Its not shrapnel because it has a formed shape.

whats the width? only thing I can think of is that they could be bits of compression rings

My guess would be part of the timing chain tensioner guide that broke off and made the journey into your oil pan.

Edited October 17, 20213 yr by DatsunZGuy
Added photo

I can see that too. The beveled edges in this screen grab is what makes me think that.

A compression test would be next for mea 

The rings aren't beveled on both sides. I forgot about that. Sorry.

Edited October 17, 20213 yr by siteunseen

For 2 seconds i thought rings too but....1. Its the wrong shape 3. Too small, its tiny 3. Compress is 185 in all 6. Iam guessing tensioner.

They don't look like metal.  Looks like wood splinters from somebody's timing chain wedge.

They are magnetic.

On 10/17/2021 at 11:49 AM, DatsunZGuy said:

timing chain tensioner guide

You can see a lot of the timing chain parts with the valve cover off.  Get a bright light and see what's down there.

If somebody broke a bolt off in the thermostat housing (very common) and drilled it out they might have drilled a hole in the guide.  It's right behind one of the holes.

I don't see how piston ring parts get out of the ring groove and down the length of the piston skirt to the crankcase without major piston damage.

This would help be for you take it apart.

https://www.harborfreight.com/telescoping-mirror-7361.html

I'm voting that it's cast iron flashing from inside the block.

I just de-flashed mine because I was able to break off a piece with light finger force.  Broke out the die grinder and had at all of it.  While I was at it, I smoothed up some cast holes for better coolant flow.

I had first-hand experience of chain tensioner parts finding their way to the oil pan. Found this in my L20b when I took it apart to rebuild a couple years ago. Not certain if that's what you are looking at, but yours look much smaller and hopefully didn't do as much damage on their journey between the front cover and oil pan if so.