What does the sparkplugnose look like? Did you check fuellevel in carb #1. If fuel doesn't reach the bowl and you suspect a sticking floatneedle, tap the bowl with the stub end of a screwdriver. Maybe floatneedle frees itself. If not, floatbowl #1 on your model is easy to remove with the rack still in situ. You could check if pilot jet is still in it's place and hasn't dropped (happened). Is the tiny O-ring around the mainjet still OK and does it seal well? If not, too much fuel will be sucked up around it.
All this can be done by just removing the bowl and leave the carbrack in place. Here's how to do it.
1. Unscrew the 4 floatbowl screws (I advise them later to be replaced by same size allen screws)
2. Pull floatbowl carefully downwards in a straight line.
3. Remove springleaf
4. remove float by carefully(!) extracting it's swivelpin. Do not exercise force. Some manage to break their whatever it is called (towers?). If the swingpin is hard to extract, spray some WD-40. Caution: whilst removing the float, have your free hand cupped under it to collect the tiny floatneedle that will fall down. Don't loose it! They are expensive.
5. Pull the main jet using your thumb and finger. Some wiggling does it.
6. After removing the main jets twist the throttle wide open in order to raise the slides and with them the needles. Now with your free hand insert from below a match or wooden toothpick into the needle jets (aka emulsion tubes). When that is snug in the needle jet, cant or turn the wooden toothpick a mm or so and you can wiggle the emulsion tube out easily. Some WD-40 at forehand can help. Essential in this procedure is that you open the throttle to have the needles raised. BTW, sometimes the needle jets just drop by themselves after the main jet is removed, so start with your hand cupped under it.
7. Use a small screwdriver 'slid in sideways (horizontally)' to unscrew the slow jet. Think first and make sure you turn it in the right direction. Gently!
8. Now all parts can be inspected and cleaned. Don't forget to carefully inspect the tiny O-rings that seal the main jets.
9. Install in reverse order. Do not overtighten the slow jets!
10 Install floatbowl using new little allen screws instead of the old dreadful crosshead screws. Much easier for future removals.
You need to be at ease and well concentrated. Don't hurry. Make it a Zen exercise . I can do it blindfolded and after the first time so can you.
This method can be exercised with 022A, 069A, 087A, 627B, 649A carbs.
