Our SKV50AD1 pump has been running longer than normal. Usual running time is about 10 seconds. I find lately it has been running for 20 or more seconds. You can hear the check valve close which I think means the water has been pumped out but the pump keeps running. Before I tackle the messy job of removing the pump I was just looking for advice on what to do. I already tried moving the pump a little and it did not seem to help much. Thanks in advance.