If there is no hint of any firing at all, then it sounds like no fuel in the float chambers, given that you have a good spark. When you primed the carbs with the lever on the mechanical pump, did the lever go "slack" as it should when the float valves shut ?
With the mechanical pump, when priming by hand, you should see the fuel level rise quickly in the glass dome until it reaches the brass gauze filter.
If that doesn't happen, then:
Try switching to reserve, even if you have plenty of fuel - there may be a split in the main pickup tube in the tank, above the fuel level, causing it to draw in air.
If that doesn't work, then try using a tube directly from a container (with some petrol in it) to the input side of the pump, to eliminate blockages, or air leaks, in the supply line.
I think there should be a choke connection on all three carbs.
|