80's Mercury won't turn over after replacing water pump

[KevMiller]

80's model Mercury 50 hp 2troke 4 cyl won't turn over, replaced water pump and it is spitting water, it's getting fuel but when we try to start it, it turns but will not start and run. Before we replaced the water pump it would run a around 5 minutes and then not start. The wires on the neutral safety switch were frayed and we replaced. I just bought the motor a couple months ago and don't know much about them.