I HAVE A 1990 FORD F-150 XLT LARIAT AND I'M HAVING TROUBLE KEEPING ANTI-FREEZE IN THE EXTRA COOLANT RESERVOIR. I SMELL HOT ANTI-FREEZE SOMETIMES AND USUALLY THE RADIATOR ITSELF CHECKS FULL. WHAT DO I NEED TO LOOK FOR TO FIX THIS PROBLEM. ANTI-FREEZE IS DRIPPING ONTHE HOT MOTOR SOMEWHERE I GUESS TO SMELL IT. IT DON'T GET HOT ANY ON TEMP. GAUGE . HOW DOES THIS OVERFLOW RESERVOIR WORK AND WHAT SEEMS TO BE MY PROBLEM?? THANKS RANDY