[Rick Parker]

dirwin:
I think you will find that the throttle plates on the suspect cylinders are not uncovering the idle ports in the throttle bores, causing no fuel to be pulled. To verify this, disconnnect the interconnecting links and the center pull. Each carb will then be independent, none will be connected to another (this is important). Then slowly twist the idle SPEED screw on the suspect carbs. When the throttle plate uncovers (creates a vacuum) over the port, fuel will be pulled and the cylinder will begin to fire.
If these are used carbs (symptoms indicate this) you will need to verify (correct as necesssary) the throttle plates are exactly the same in relation to the idle port when viewed from the bottom. Use a magnifying glass for this. You may also need to very slightly twist the throttle shaft to accomplish this.
The same syptoms can exist if you have bad valves on the suspect cylinders, but if the engine is relatively new, then the above is your issue. Go slow......
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