Quick BS34 Carb Question

[bdholsin]

Real quick question on my BS34 carbs. I recently cleaned the hell out of them. Stripped the black paint off and reassembled (properly I might add). I'm having a little issue with fuel pouring out of the right hand carb. I know for a fact that my floats are both set at 22 mm. I just did that today. However, I'm still tinkering with the mix screws.

Here's my question: if I have the mix screw on one carb (the right hand one in this case) backed off too far would that allow fuel to flow more freely into the carb bowl and subsequently pour out of the back of the carb? I believe it is coming from the jet in the lower left hand side of the face (as you are looking at it from the perspective of the air filter).

I just got back from a quick test ride and it did this. I had the mix screw at 3 1/2 turns. Brought it back to about 2 1/2 turns and it seems that the fuel has stopped flowing out of the carb.

I realize it could be the o-ring in the needle valve seat but I just replaced it this weekend. There is the possibility that I nicked the o-ring or that it was damaged from the get-go. However, the mix screw adjustment fix leads me to believe that it isn't the o-ring.

Am I going in the right direction here? Thanks guys.

 

[azman857]

When the carb was mounted on the engine, did you tap the float bowl to see if the floats were stuck open. Most times it frees up the float to let it do it's job.The mix screw has nothing to do with fuel flowing inot the float bowl. Only idle mixture and partial throttle.

 

[jayel]

float stuck/sunk or bad needle and/or needle seat

 

[bdholsin]

I didn't tap it at all. Maybe the float was indeed stuck.

I put new needles in it back in October.

 

[bdholsin]

So I'm guessing that my float just stuck for a little bit and spewed fuel through the carb. Seems to have resolved itself. Perhaps it was stuck because it was completely dry when I reassembled it and it just needed fuel to lube it. Who knows? I did put new needle seat o-rings on both carbs. When I do this I use a tad bit of oil to lubricate the o-ring so it doesn't get scuffed as I slide it into the housing.

The floats are good...meaning they don't have any holes and are filling with fuel. This last little bit of tweaking is driving me nuts. I want to ride...not take her apart again. Sheesh!

Thanks for the suggestions.

 

[gggGary]

BD are your floats brass or foam?

 

[AirsoftNY]

The left side on my BS34s does this quite often. Once I turn on the petcock, fuel most likely will start to come out out the carb's air filter. I'll turn off the petcock and give the bowl a few taps with the handle of a screwdriver and start her up. I think the engine's vibrations shake the float needle loose and once the engine is on, that carb stops leaking. I chalk it up as one of my XS's many little personal quirks.

 

[bdholsin]

Gary, they aren't brass...they are plastic (or foam as you indicated).

Airsoft - Our bikes seem to share some quirks.

 

[gggGary]

My Farmall H works the same way fuel on for about 30 seconds shut off fuel befoe it starts to pour on the ground, start tractor then fuel back on.
If the tank isn't sealed and all fuel components replace a little fine rust will do that. If you are waking a bike from a long nap a few drain offs of the float bowls may help get the last junk out of the system. Sometimes you just have to put in new float valves.