On 23/03/2018 14:06, Harry Bloomfield wrote:
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.

In mine, there is certainly a weak spring which must be overcome first,
but I agree it is nothing like the "wavy washer" system in an ordinary
hammer drill. OP's problem doesn't sound like a broken spring to me,
more likely something clagged up with dead grease and stone dust.