I'm stripping down the engine I knocked a big end out on 2 years ago.
The oil in the heads has tiny slivers of steel in it, from the destroyed big end shell I assume.
Why didn't the oil filter catch these bits, or are they smaller than the filters capabilities.
Blueprint filter.

 

Think about it, crank is revolving, oil flows from the crank pin through your failing big end, taking the small particles of bearing in the oil mist, your heads house your breathers, thats where the mist is rising too, dropping particles on the way.
The filter only protects the oil gallery feeds, after that any failure mode is fair game to go anywhere it wants.

 

 

but the silvery stuff was in the oilways in the head, and they can only be filled by the pump via the filter?

 

When the filter is blocked it will go via the valve in the bottom of the filter.

 

That sounds more likely, never thought of that

 

The filter is only good for picking up small carbon deposits & small pieces of contamination. What tends to happen when the bearing fails is initially the fragments of the bearing get pumped around your engine, then the pick up pipe in the sump gets blocked & starves the engine of oil. So make sure you fully clean EVERYTHING inside, especially the small oil jets. They easily get blocked.

 

It's being stripped to the last nut and bolt. I'm doing the heads first.
All oilway plugs and oil resrtictors are removed, everything will be thoroughly cleaned.

Thanks for the info fellas!