Thanks for staying with the case Guys. I cleaned and rebuilt the carb's. Couldn't find any dirt in them. Replaced the bowl on #3 because of a bad drain thread. Refitted the carbs and and checked that fuel was getting into them. Took it to the pond and it ran strong on the ramp, much better than before. Launched and opened her up. Bingo! 5500K rpm and running smoothly.
My only guess is that fuel was getting past the string seals into the carb throats and not filling the carbs. If anyone has a better explanation I would be happy to hear it.
My only guess is that fuel was getting past the string seals into the carb throats and not filling the carbs. If anyone has a better explanation I would be happy to hear it.