Gary, the bb i am talking about is located in the bottom of the accelerator pump well. they were only used on the end carbs in 58. it's alum and i think it was 5/32 in dia. all three of your carbs should not have this ball in the bottom of the accelerator pump well. the pump discharge check ball, higher up in the main carb body stays in place on all three carbs. it's steel and 3/16 in dia. it's under a light spring held in place with a tee shaped retainer.
The first thing,,,,are your carbs original three two carbs?? If not you are in trouble from the get go.
Gearhead is correct, aluminum check valves in the bottom of the accelerator pump well is installed in the front and rear carbs only. A lot of times the aluminum check ball will become stuck in the front and rear carbs, it's a bear to get out. There is no aluminum check ball in the center carb pump well. Don't get the pump well check balls mixed up with the pump discharge ball check. Also as stated earlier there is no power valves in front and rear carbs. Your flooding problem is caused by one or two things, either you have dirt in the idle circuit or (most likely) your fuel pump pressure is overcoming the float needle and seat. 4 lbs max should be the pump pressure to the carbs. Also stated earlier is the suggestion that front and rear carbs may be leaking air past the throttle blades. The front and rear carbs on an original three two setup had throttle blades that are different from the center carb, they are thicker to prevent them sticking in the throttle bore when they are closed. Center carb is never closed all the way. Float level adjustments are, Float level, front and rear carbs, 1 5/16". Center carb, 1 1/4" Float drop, all three carbs, 1 29/32. Hope this helps. I cannot comment on the jetting at different elevations. I jet my three two's for the 348 with .061 jets front to rear.
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