5.7 Runs on muffs, not on the water

[paston1]

Wanted to freshen the runabout motor up. New camshaft, new edelbrock carb and intake, new mallory distributor and coil. Only thing not marine grade is the cam and it is a very mild street cam. The thing runs like a champ on the muffs, but as soon as she is in the water it starts very hard and wont stay running and then it wont restart. Pull it up the ramp hit the key and it fires right off? I am baffled need input

 

[imco offshore]

check the floats in the carb ,,maybe they are at the wrong angle when the boat is floating in the water,,!! good luck

 

[paston1]

It could be the floats. Only confusing part is in my experience in flooding issues once it floods and you go to restart it will usually blow a little black smoke or it is hard to start. I can pull it right back up the ramp and it will fire in half a revolution. The only thing that keeps going through my mind is backpressure as it seems to be the only variable. I appreciate all your help and all input is appreciated. I will check float levels tonight.

 

[imco offshore]

it could be the opposite ,,instead of flooding ,,maybe its closing the fuel,,then when you pullit out of the water their is just enough fuel to fire it off ,,and the fuel pump can fill the bowls rather quickly to keep it running, I remember working on chris crafts that usto use those carbs ,,but they had a wedge between the carb and manifold to level the carb ,,

 

[Ratickle]

If it stays running on the muffs, I think George is at the right place to start looking.

When you go to restart in the water, does it turn over the same as on the muufs? Or does it turn over easier or harder?