strip it down to its component parts and check them for damage, replace anything that does not look right, check the piston head for damage also such as a deep scratch and the piston wall as this would have taken a significant amount of damage. anything with a dent, deep scratch, needs to be replaced, you will also need to thoroughly clean the engine out to remove partials that will now be in there, check the cylinder head for damage also. always a issue with IC when something goes wrong it costs more to fix then you expect!
if you engine is anything like mine on the con rod i have a 'micro super charger' looks like a fan, check that there is no cracks around the part or on the bearing housing, i had a flooded engine once and over pulled it with the force of the pull and hydraulic lock up it shattered the cod rod and the super charger. now i will never use and electric starter back to the old rip cord!