Status of Blood in Meat
Blood is generally forbidden to be eaten. However:

• Blood that has not moved from where it was in the animal before the animal was killed may be eaten--but only if eaten raw.
• Blood in veins and arteries may not be eaten.  If meat is cooked with this blood still inside the meat, the meat is non-kosher. (During kosher butchering, the main veins and arteries are removed.)
• Capillary blood is permitted once the animal is dead. 
• After meat has been salted, even if pink liquid comes out, the meat is still kosher.

Kashering Meat by Broiling after Three Days
Normally, meat must be soaked and salted within three days of being slaughtered.
REASON The blood may have solidified by then and will not be completely removed by salting. If you were to cook such meat, the blood would move and the meat would become non-kosher.
But, even after three days, you may broil or grill and then EAT the meat, as broiling forces out any blood that will come out. But you may not then COOK it afterward.