George Miles brought next idea :
My DeWalt SDS drill turns but doesnt hammer.
Someone siad there's a spring inside which I may have broken by pushing hard
on the drill trying to drill down through concrete.
Hpw easy are these things to repair,
or shall I keep the plug and lead and dump the rest?

So far as I am aware, there is no spring and you should not need to
push SDS, they work by the bit bouncing off the hammer. The bit ends
are supposed to be cleaned off and greased, before insertion in the
chuck. No grease, means the bounce does not happen.