Suspect the vertical jet hole in the float bowl nut is not completely open. Probably just a little build up on the edges of the hole. You likely used a twisty wire to probe the hole already, go back with it again and work it up and down while angleing it so it rubs the hole sides.

Also check the throttle butterfly shaft for wear. A little up and down play is alright but if it has any side to side wobble when trying to with the shafts bellcrank there is wear. This allow air to pass into the throat and at this point the air has no effect on drawing fuel so it runs lean. Now keep in mind when this happens both the shaft and the hole in the carb body have worn but if the shaft has never been replaced before, replacing the shaft and will usually correct. If shaft has been replaced before the hole in the carb will have worn so bad that the entire carb will need replacing.

Couple of final thoughts. The o-ring sealing the carb to the intake plate, make sure it is still there.

If fuel tank wasn't cleaned and fuel line wasn't replaced you could still be getting stuff into the carb. You did say it ran fine after the first basic cleaning so this has to be a consideration.

Bob
Last Edited By: NevadaWalrus Oct 22 08 3:54 PM. Edited 1 times.