Ford: serpentine belt tension, 89 ford thunderbird, replacing a water pump

Question
Hello, I am replacing a water pump in my 89 Ford Thunderbird.The old water pump had a destroyed bearing in it which leads me to believe that the tension on the belt was too high.Can you tell me what it should be and how do I measure the tension?

Answer
yes if you look on the tensioner you will see markings on it one on the back side and 2 on the front if the back is not  in between  the front one then it's time to replace it also if you use a tension tool to releace the belt and you feel it pull to easy then just change it .we change ours tensioners if the vehicle has over 60,000 miles is a good rule of thumb.