I noticed my car running a little warmer than usual today and when I raised the hood the reservoir was still full of water. Normally it would be low. Checked the radiator and had to put about a half of gallon of water in it. What is keeping the water from going from the reservoir to the radiator? Also, can't fiqure out where the water is going. When I park it there isn't any water leaking out. Thanks, R.B.