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  5. Won't Start
Won't start unless I pour gas into the carburetor.

Obviously the float bowl isn't filling up.


The electrical system won't be addressed here and assumes it is in working order.
  • To verify look down the bore and pump the gas once. You should see a squirt of gas go into the bore. If you do, then you are getting gas and should look elsewhere.
  • Test the fuel pump (even a new one) to see if it is pumping 4.5 lbs prox.
  • Look for any kinks in the fuel line. Also rubber hose could be collapsed on the inside.
  • There isn't much room around the float and they can rub on the side of the float bowl. You may have to bend it sideways a bit to clear.
  • Move the float up and down by hand. Does it move freely?
  • Is there a clip that clips the needle to the float? If so, be sure it pulls the needle out straight.
  • Open the needle and blow in the inlet to be sure the needle isn't sticking closed.

Hello I spoke with office and they suggested I send an email. I have seen you tube videos series on rebuilding my mid 70’s Rochester monojet which is on a 63 chevy C10. I cannot for some reason get gas to come out of the ventura. Truck runs very well once I spray starter fluid or a little gas but will not start otherwise. I have had apart several times and even used some rebuild parts with new accelerator pump.
With engine off look down the carburetor bore and pump the gas once. You should see a stream of fuel come out of the venturi.
If not:
  • Check to see if the small passages are clear.

  • Monojet Accelerator Pump

  • Take the top off. Pump the gas to see if fuel is coming out of the main discharge. This is where the #39 is.
  • Look at #39, #40 & #41. Your assembly should match.
  • If gas comes out of the main discharge then your problem is after and most likely at the venturi.
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