Mercruiser 57 Fuel Pump IssueHELP

i have 5.7 mercruiser and the

i have 5.7 mercruiser and the fuel pump only runs when the engine is cranking. Then when the key is on the run position the fuel pump stops. SO the engine only runs until it runs out of the fuel pumped into the fuel bowl. I thought it was the big canon plug on top so i took it appart and cleaned it with dielectric grease and put it back together and now there is no spark( no 12 volts positive terminal of coil) Please help. I know why i have no volts but i am not sure why the pump is not staying working after the engine fires. Thanks! DC

Look on the port side of engin

Look on the port side of engine near the oil filter. There is a switch with two wires. This is the oil pressure switch that makes the pump run after starting. Jumper them out just to test. Thn replace if necessary