Thanks Bob. The motor came apart easy! But not without me damaging the thread on the crank with a hammer frown I guess I will need to re-thread it now..

The piston was shattered in a few places and because there was loose pieces in the block, there are now 3 grooves in the chamber about .5mm deep..

Can this block be re-used or does it have to be remachined and oversize piston fitted?