87 RX7 started after month small problem...

well my RX7 had been sitting their for all winter and today it was really nice so i went out and battery was low so i connected the jumper cables and turned on the first try the only thing is that the add coolant light and buzzer are on i know its not the sensor becaus its new but i also added coolant and still goes on but if i drive it around it will sometimes go off and come back on someone told me to drain the radiator what does anybody recommend i do i will also replace the thermostat while in the process....

Sounds like an air bubble is in the cooling system. Have u tried filling the system with the bleed screw near the filler neck removed?

yea well that is fixed but i found another problem the housing of the water pump where the thermostat housing goes has a crack in it and leaking alot of coolant trough their i need to replace the water pump housing know would this be hard....