Okay, I learned something today. I have always said that PAJ2 is blocked off at idle and only opens at off-idle throttle angles similar to the piston slide. I was WRONG.
I did an experiment using a straw on one of my spare carbs. I originally was going to mention suck and hole but figured I would get Lankee all hot and bothered. Sometimes a burrito just doesn't keep him from humping your leg. Anyway, I could get air through PAJ2 with the plunger all the way in the bore. If I pulled it out a tad then no air would go through. I looked at the plunger itself and the very tip of it is what closes PAJ2. If you look at the included picture you can see the end is thicker than the rest of the plunger. So, the coasters actually open to close off PAJ2. Normally, air would go from the air vent at the top of the carb (same vent used to open slides), go through PAJ2, go around the thin part of the plunger and on to mix with pilot fuel. There's a small passageway that leads from below the butterfly to below the enrichener cover. When you close the throttle at high rpms there is high vacuum and thus low pressure. So, low pressure signal travels up the enrichener port and the PAJ2 air pushes on the diaphragm to open and closes off PAJ2. So, the only time the enrichener opens is at high vacuum. When you chop the throttle off at high rpms it pulls the enrichener open which closes PAJ2. When the rpms drop to a sufficient level then the enrichener closes which opens PAJ2 again.
I learned something today, I can have a beer now.
Mark
I did an experiment using a straw on one of my spare carbs. I originally was going to mention suck and hole but figured I would get Lankee all hot and bothered. Sometimes a burrito just doesn't keep him from humping your leg. Anyway, I could get air through PAJ2 with the plunger all the way in the bore. If I pulled it out a tad then no air would go through. I looked at the plunger itself and the very tip of it is what closes PAJ2. If you look at the included picture you can see the end is thicker than the rest of the plunger. So, the coasters actually open to close off PAJ2. Normally, air would go from the air vent at the top of the carb (same vent used to open slides), go through PAJ2, go around the thin part of the plunger and on to mix with pilot fuel. There's a small passageway that leads from below the butterfly to below the enrichener cover. When you close the throttle at high rpms there is high vacuum and thus low pressure. So, low pressure signal travels up the enrichener port and the PAJ2 air pushes on the diaphragm to open and closes off PAJ2. So, the only time the enrichener opens is at high vacuum. When you chop the throttle off at high rpms it pulls the enrichener open which closes PAJ2. When the rpms drop to a sufficient level then the enrichener closes which opens PAJ2 again.
I learned something today, I can have a beer now.
Mark