Fuel Pump or Carb problem
Posting Guru
Joined: Jun 2004
Posts: 1,635
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From: Niceville, FL.
BOOYAH,
I'm assuming the engine will start and run fairly normally at idle. First (with engine off) remove air cleaner and hold the choke flapper open with your left hand and look down the throat of the carburetor. Move the throttle from closed to wide open several times using your right hand. Each time you move the throttle linkage you should see two streams of gasoline (one for each of the front two venturi (barrels) squirt downward. If not, your accelerator pump may be bad. Second, remove the sight hole plugs (one for each float bowl, passenger side) and check to see if there is gasoline even with the bottom of the sight holes especially on the front float. If some runs out when the plug is removed then the float level may be a little high. If none is visible you may need to use a probe of some kind (a tobacco pipe cleaner works well) to get an idea of what the fuel level is. If it is more than 1/16" inch below the bottom of the sight hole you may have to raise the float level. Do these tests and post what you find.
I'm assuming the engine will start and run fairly normally at idle. First (with engine off) remove air cleaner and hold the choke flapper open with your left hand and look down the throat of the carburetor. Move the throttle from closed to wide open several times using your right hand. Each time you move the throttle linkage you should see two streams of gasoline (one for each of the front two venturi (barrels) squirt downward. If not, your accelerator pump may be bad. Second, remove the sight hole plugs (one for each float bowl, passenger side) and check to see if there is gasoline even with the bottom of the sight holes especially on the front float. If some runs out when the plug is removed then the float level may be a little high. If none is visible you may need to use a probe of some kind (a tobacco pipe cleaner works well) to get an idea of what the fuel level is. If it is more than 1/16" inch below the bottom of the sight hole you may have to raise the float level. Do these tests and post what you find.
Senior User
Joined: Jul 2006
Posts: 396
Likes: 0
From: Eureka, KS
Did the new fuel pump come with carburetor float adjusting gnomes that ran up the fuel line after you eplaced it and changed your float level? or any other settings on the carb for that matter.
Looking at it logically, You didn't seem to have any symptoms, you replace the fuel pump and the metal line with a rubber line. Now you have this symptom. Why would the carb be out of adjustment all of the sudden? The only thing you changed about the setup was the line from pump to carb.
You have to make sure the work you did is right before moving on to other possible causes.
Nothing wrong with checking the float level. Can't see why it would've changed if someone didn't change it. Your fuel level in the bowl could be high, higher than the float level should allow it. That goes back to high fuel pressure, which either goes back to the rubber line or the new fuel pump is putting out too high a pressure.
Looking at it logically, You didn't seem to have any symptoms, you replace the fuel pump and the metal line with a rubber line. Now you have this symptom. Why would the carb be out of adjustment all of the sudden? The only thing you changed about the setup was the line from pump to carb.
You have to make sure the work you did is right before moving on to other possible causes.
Nothing wrong with checking the float level. Can't see why it would've changed if someone didn't change it. Your fuel level in the bowl could be high, higher than the float level should allow it. That goes back to high fuel pressure, which either goes back to the rubber line or the new fuel pump is putting out too high a pressure.
Posting Guru
Joined: Jun 2004
Posts: 1,635
Likes: 0
From: Niceville, FL.
Maybe I'm wrong, but I thought changing the fuel pump and line was the first attempt at fixing the problem. And he says he is sure fuel is getting to the carb, so maybe the problem has been in the carb all along. All I wanted him to do was make a couple of quick, simple checks so we'd be able to eliminate a possibility or two. I just can't see where a rubber hose (fuel hose) on the pressure side of the pump would cause the problem.
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