kenmore icemaker

I have a kenmore fridge that was bought in 1997. It did not come with an icemaker, so we bought an icemaker kit and installed it. It has worked perfect for about three years. Now it want do anything. We replaced the icemaker and the water inlet valve and checked the tube going into the icemaker to make sure it was clear and it was. After three days still no ice. I know it has power going to the icemaker but still wont make ice. Any ideas? Thanks,Don.