Late 1970's carb float bowl question

[meyekj]

Can someone confirm that the small hole inside the float bowl (center of the photo, not the drain plug) and it's mating location under the gasket surface is supposed to be plugged on a late 1970's BS34 carb? I've thoroughly cleaned the passages, but it looks like there's brass plug inside to block it. I assuming this is a through passage in a different configuration. Hopefully my description and photo make sense. Thanks.

 

[meyekj]

I should mention these carbs originally came off a '77 XS750. The only differences I know of (besides having bank of 3 instead of 2) is the jetting. I believe this/these holes I referenced above are part of the choke/enriching circuit, but I'm often wrong...

My bike is a '78, but the PO but mid-80's carbs on it so I don't have a good reference since the float bowls differ slightly. Thanks, again.

 

[xschris]

That passage (on the xs400 carbs ) should be clear to allow fuel to flow through it.

 

[meyekj]

Thanks! I thought it seemed odd when I was cleaning it.

 

[meyekj]

Does anyone have a photo of your xs400 bs34 carb float bowl I could use for comparison? Does the xs400 bowl have the channel in the gasket surface? What is that for? Based on my recollection, that vents to the top of the bowl via another passage, right?

 

[xschris]

This is of a 77-79 xs400.

 

[meyekj]

Perfect! Any idea what the diameter of the vertical hole is at the bottom where it meets the 45-degree hole? If it's much smaller at the bottom than the top, it could be that it's just not clean yet. If it's a consistent diameter I can drill it out. Thanks, again, xschris!

 

[xschris]

Don't drill anything!!!! Use a fine wire or compressed air to clean it out.

 

[meyekj]

So after another attempt (and flashlight and magnifying glass), I saw that there was a small hole. More carb cleaner and a fine wire, as suggested, did the trick. Thanks, xschris!

 

[xschris]

Good deal Glad you got it.