So my 1987 mercury 150 is having some issues. When starting it for the first time it doesn't want to stay running. After it fires if I give it gas from the hot foot it runs. It'll do this until I let off the pedal. The entire time my beepers are going off as if the motor is not getting water. Impeller was just replaced last month. Once I get the motor to idle on its own I attempt to put it into gear and it falls flat on its face and dies. I did notice however today that once the alarm shut off the motor ran fine and would run like normal. Any of you mercury guys have any ideas as to what my issue could be? The carbs were just cleaned last month, new plugs and plug wires last month, fuel is fresh and has purple stabile in it, fuel lines were changed last month, impeller is new. Once it get it running good its runs like a brand new engine. Any help at all? Thanks