I've got a Mercruiser replacement engine a couple of years ago that had an electric fuel pump installed Carter 152-875. There are 2 leads, 1 ground, 1 power. The ground lead was attached to the water pickup pump. So yesterday, I did the yearly replacement of the impeller after the boat sat for the winter. Since there's a slide connector to the electric fuel pump, it's easier to disconnect the ground at the fuel pump then at the water pickup pump. So new impeller installed and go to put it back on when I noticed that power lead to the electric fuel pump is also disconnected. Not +/- indications on the electric fuel pump. So how do I connect it? Does it make any difference, is the pump just a diaphram the pulses on/off? Couldn't find anything on Carter Web site. Thanks for any help.