Years ago, I replaced the radiator cap on my 1954 Buick. A couple weeks later, the radiator started leaking so I had the radiator repaired (this was in the days when radiators could be repaired). After the radiator was repaired, the water pump started leaking. All were related–when the radiator cap was replaced, the system developed the presssure that it should. This pressure caused the radiator to leak, partially relieving the pressure. When the radiator was repaired, the next weak spot was the seal on the water pump. After all these things were fixed, the cooling system required no more repairs as long as I owned the car.