Air screw o-ring size

[Bonz]

Guys,

Just pulled my carbs and cleaned them on my 80 SG. Put them back on the bike, and get fuel coming out #2 carb into airb box. It's ONLY when the engine is running, so I know it's a carb issue, not petcock/diaphragm related.

When I took the carbs apart, I took off the caps to the airscrews and removed the "screws", springs, washers, but didn't realize there were o-rings in there. Once done cleaning, I noticed the o-rings down those holes, and #2 was missing. It obviously got lost in cleaning, and no possible way to find it! I got the airscrew re build kit for a mikuni 34 carb from Mike XS, and the o-ring is a good bit smaller in overall diameter, but the thickness seems the same and the hole size seems the same as well to my naked eye.

So, I put the carbs on and it is leaking fuel out #2 as described above. Could this o-ring be in any way related to this? I say NO, but just wanted to ask.

It's a bummer to clean everything and re-assemble (set float height for correct level according to supplements in shop manual for 80 SG, so they started out being set correctly when I put the covers back on) only to have it burping fuel.

Let me know if you think it's simply a float needle not seating, or if there is anything else I should check that I wouldn't have found elsewhere on the forum.

[foreda]

Float valve

My bet is on the float valve not seating.

[DGXSER]

IF you still have the Octy on the bike, that is why it only leaks when it runs. At least that tells you your Octy is owkring properly.

Sounds like a float needle valve to me. You can try wrapping on the float bowl with a screw driver handle or the like. Otherwise, I would say you got something in the screen that got to the needle or the gasket is catching the float. I had to trim the gasket sides to match the bowl on mine.