Get a fuel pressure gauge, and T plumb it in between the carb, and fuel
pump. Mount it where you can see it while running, then stalling. At
least it will split the fuel system in half.

10-20 seconds later, she instantly cuts off.

It really sounds like a fuel problem.

1. Some carbs also have a small filter where the fuel line goes into
them. You can usually tell because there is some sort of removable
fitting on the carb where the fuel line attaches. Check for this.

2. Electric fuel pumps often have a mechanism that shuts them off if
the engine is not running. Typically this is bypassed by the starter
circuit so the pump engages where cranking. Connect the pump directly
to a 12v source to see if this is your problem.

3. Boats have a check valve in the system to prevent the gas from
leaking out in the case of the boat getting turned over. This is most
commonly a ball and spring check valve where the fuel line comes off
the tank. There is also sometimes a screen on the pickup line going
into the tank. Boat tanks tend to get more trash and corrsion in them
than cars. Try connecting a piece of hose directly from the fuel pump
and putting it down in a plastic gas can to see if there is a supply
problem.



den wrote:
Get a fuel pressure gauge, and T plumb it in between the carb, and fuel
pump. Mount it where you can see it while running, then stalling. At
least it will split the fuel system in half.

10-20 seconds later, she instantly cuts off.

FYi,

The end result was a bad oil pressure switch that kept shutting the
fuel pump down after 10-20 seconds!!


jamesgangnc wrote:
It really sounds like a fuel problem.

1. Some carbs also have a small filter where the fuel line goes into
them. You can usually tell because there is some sort of removable
fitting on the carb where the fuel line attaches. Check for this.

2. Electric fuel pumps often have a mechanism that shuts them off if
the engine is not running. Typically this is bypassed by the starter
circuit so the pump engages where cranking. Connect the pump directly
to a 12v source to see if this is your problem.

3. Boats have a check valve in the system to prevent the gas from
leaking out in the case of the boat getting turned over. This is most
commonly a ball and spring check valve where the fuel line comes off
the tank. There is also sometimes a screen on the pickup line going
into the tank. Boat tanks tend to get more trash and corrsion in them
than cars. Try connecting a piece of hose directly from the fuel pump
and putting it down in a plastic gas can to see if there is a supply
problem.



den wrote:
Get a fuel pressure gauge, and T plumb it in between the carb, and fuel
pump. Mount it where you can see it while running, then stalling. At
least it will split the fuel system in half.

10-20 seconds later, she instantly cuts off.