Mercury 4 stroke fuel issues

[Jepruitt80]

Hello, to all. I’ve used yalls brains and experience before but I’m stumped. I’ve got a 2012 mercury 115 4stroke. It’s having the fairly common issue of crank it up, runs fine for a minute or two, falls on its face and eventually dies. So far, I’ve replaced the float switch, lift pump, seals, and fuel line in pump tank. If I start it, I get a long beep after 30secs or so. Also, I have a kicker motor with a bulb on it and if I hook that line to it a squeeze the ball some it’ll keep running. Any ideas? Thanks

 

[DeepCMark58A]

Sure sounds like a fuel pump.

 

[Jepruitt80]

Are you thinking the high pressure pump or the lift pump?

 

[wrench 3]

It's time to check fuel pressures and see what's going on.

 

[Jepruitt80]

Seems like most of the time it ends up being the float switch. I had just bought one at a marina. Do you think it may be wrong? I’m not sure what part number it is. Thanks

 

[puddle jumper]

I don’t know your set up but if your kicker and main engine both run off of the same fuel line from the main fuel tank. You may be starving your main engine from pulling air through your kicker fuel system

 

[Jepruitt80]

They’re completely separate systems. Thanks