(not) BS34 um BS38 carb bowl question

[ThatXS650Guy]

Hey Gang, I took the carbs out again for another cleaning. I had it running after sitting for 20+ years but it wouldn't idle off of choke. Here is what it looked like before the first cleaning:

That black stuff is old gas and was as thick as cold molasses.

Here is my question. I have ensured all the passages are clean with this one exception. I can't seem to get any air or carb cleaner through it. I am not even sure where it is supposed to go. Here is a pic:

Where is does this feed? When I fill up the bowl all the places that are supposed to get fuel do. The enrichment well and the main and pilot jet wells. But I can't get anything thru this particular port and I can't really see where it is supposed to go.
TIA,
Jim

 

[gggGary]

Nowhere, on some models of the BS38 there is a brass overflow tube in that port.

 

[oldcoal]

I had the same sort of problem on my new to me 82 XS650. It would idle if choked but not take any throttle with out dieing. I had the carbs open and cleaned them but still the same thing. I took the air cleaner back off and use a torch tip cleaner tool in the 4 holes in the air intake area of the carb to poke out the holes then spray carb cleaner in to them and it now runs a lot better and takes throttle but still not 100% yet

 

[ThatXS650Guy]

Ha Ha so they are BS38s? My manual says they are BS34s but I cannot see a mark on them either way.

Thanks gggGary! I would have been squinting at that hole for hours trying to poke a wire thru it.

 

[gggGary]

Do a hot water dip test on the floats. Just submerge them in hot water for a couple seconds, bubbles = fail, on my carb bench over half the brass floats fail.

 

[oldcoal]

I have messed with carbs for decades and found years ago you can spray a case of carb cleaner into hole but if that is will you do it does little good unless you also poke them out. I use a torch tip cleaner tool since it has a number of size wires so you can start small and work your way up bigger till they no long fit

 

[5twins]

Yes, it looks like you have a set of '78-'79 BS38s there.

 

[weekendrider]

Torch tip cleaners would tend to eat into the hole wouldn't they?

 

[gggGary]

Torch tip cleaners would tend to eat into the hole wouldn't they?

I'm with WER on this; nothing but copper wire in jet orifices for me. I pull strands from a selection of stranded house and automotive wire. For really fine holes once the copper strand is through I "wrinkle" it a bit and pull it back and forth, along with carb cleaner it seems to do the trick.
I will confess I find final tuning seems to settle down after a hour of so of use, I think modern gasoline typically "finishes" the cleaning and dissolves/flushes out what we cannot reach.

These BS34's were home so some very industrious mud daubers. EVERY hole was plugged and most had larvae in them.

One slide was the hardest I have ever had to work to remove, wasp spit is good glue! I got it out with no damage, diaphragms are in great shape! I made a curved wedge out of some nylon with a slot to go around the needle and had to drive it in several time before the slide stated moving, then lube tap it back down, lube wedge open a bit, repeat til it came free. A bit of carb cleaner and some 1500 grit and they move smoothly now.





All that was under the diaphragms!



While rock climbing at Devils Lake yesterday 10/22/14

 

[oldcoal]

I have never had any problems with them opening the jet up more but you also should not get real aggressive when your cleaning them out