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Haven't driven boat for longer than 10mins after I got it

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WHOGONZO

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Hey guys newbie to ever having a boat and to this forum. I need help cause I still haven't got boat out for longer than 15min since I got it as a gift. Now I got to get her running so I can take kids on it. Well enough of a that. I have a old 1983 cuddy cabin with a Mercruiser 470. When I first got it boat would turn and stay on but after running it for about 15min it stalled and did turn on again. Had to get towed in that day. I also turn boat on a few times on water and it stayed on for about 10 minutes and did want to start again. So I tried rebuilding carb and fuel pump, well failed fuel pump cause it wasn't pumping so I decided to get an electric pump. I got a carter, which I installed with a relay and a oil pressure switch. Now the pump just over flows the carb with gas and drowns it. I can't figure what to do now. How can I control the flow to carburetor? Did I do something wrong. Do I need another part? Maybe something with carburetor? Please help. Thank you guys.
 
The new pump may be providing too much pressure. I would think 4 to 5 PSI would be about right for your app, however, my recommendation here would be to install the correct mechanical pump for a couple of reasons. First, it is designed to provide the correct pressure and volume and second, there is a safety designed into the pump with I doubt your electric fuel pump has. Should the mechanical pump have a ruptured diaphragm, it is plumbed to feed into the carb...for safety reasons. In reality, its really best and safer to use "original" OEM parts...or equivalent aftermarket parts on a marine engine.
 
Are you sure you rebuilt the carb correctly? A float that's stuck open will flood the carb. That was my first thought anyway.
 
Welcome to boat ownership, however you are learning that no boat is a "gift", but can be lot of fun.

Note, the 470 engine is unforgiving of any neglect, overheating, or poor maintenance. Religiously check the coolant level and oil EVERY time you use it. It has a cast iron head and aluminum block which is easily damaged if over heated.

That Carter fuel pump has about twice the pressure that the Mercrusier carb specifies, yes it will flood. You need to get a 470 manual and get parts matched to the engine specification. Manual states the fuel line pressure supply supplied to the carb is 3-6 psi.; Fastatv is right, 4 psi @ 1,000 rpm is best. Again, NEVER EVER put automotive parts in a marine application. You can convert to an electric system, but ensure the pump & set up is actually approved for marine use.

If you replace the mechanical with mechanical do not lose the original thick gasket between the pump and block. Using the incorrect thickness will result in incorrect fuel pump pressure. If the gasket is unusable, replace with equal thickness which is about 3/16" thick. It is a challenge but not impossible to find a mechanical replacement. Most replacements come with a thin gasket and your pressure will be too high again.

I would strongly advise to upgrade the distributor to Petronix ignition & coil conversion, better; starting, performance and economy. Clean and lube the advance weights, then make sure they actually work. Set your base timing to about 6 degrees and you will be able to get your in gear idle speed correct at about 650-700 rpm. Make sure your radiator cap is 14 psi., thermostat is 160 Deg and correct style.
 
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