I have a clogged oil sieve in the bottom tank and the oil pressure has dropped in the engine. This has meant that my engine has separated small pieces of metal. these metal pieces are now in the bottom tank. Is it a new engine I need? or can it be repaired?
and another qustion why does the oil sieve get clogged?

oil sieve

 

More than likely its blocked due to poor service history/missed services.

The engine will be junk. Cheaper to buy a low km second hand engine.