FFFFF... Floats...

[Sparky84]

Do the o rings now while you're there!
You only need to take outside ones off, middle 2 can stay on bracket.

It can only leak through the tube if fuel level inside keeps rising, which means float needle is not seating or it is set too high/low, which it isn't because you checked it and it was below with the clear tube.

No I didn't replace those o'rings. But it was leaking through the tube, not by the plastic connector. Everything was nice and dry when I checked the level on the bench.

Mine were fine until I moved those tubes, sitting on bench they were dry too..

Do it, replace those o rings, it'll be 1 more thing off the list of possibilities  

Before you fly south for the winter, you can have some of our warmth if you want, it's going to be early 40's on the weekend

(C not F)

[stou]

Yes I'll replace those o'rings. Like you wrote, it's better to do it while I'm there. The only reason I can see for the leaking is the level is probably at the higher limit on the bench. When I installed them on the bike, with the 6° angle and probably not on level on the driveway, that make them leak.

Sparky84, here this morning, it's -15°. A bit of warmth will be welcome next week!

[Sparky84]

they state in the manual to jack up bike so that carbs are vertical (level) then check fuel level.
You've done that on the bench to the required height, so when they go on the bike and are at an angle, they shouldn't leak..

-15 sounds nice

for a day 

[stou]

I'll recheck everything again at level and at 6° to see how it react on the bench. When I did it at level last week, there was no leaking at all on the bench. Maybe it was more at +3mm and when at 6°, they leak. We'll see!

Thanks for the picture. I only have a pdf copy of the Haynes manual.

[balky1]

This original manual also says to measure the level with engine running.
Others will have more knowledge about the importance of this step. I played and played with floats once and couldn't get them sorted so my credentials are useless. 

[stou]

Yesterday I did the floats adjustment once more. I did it at level and then checked at 6° to see how it look like. The level is lower at 6°. When I verified them again today, #1 and #3 was ok, #2 a little bit high and curiously, the #4 was very high. I readjusted #2 and then start to work on #4. On 1, 2 and 3, the tongue hight of the float was between 2.20 and 2.40mm high. The #4 was at 2.45 from the last adjustment, but leaking. I started to rise it and after many time it was looking

My setup


At level


Carb #1 and #4 at level on the bench




Today I installed the carbs on the bike and get it out to start it. The bike was running not too bad but the #4 started to leak again... WHAT!!!

I checked the level on the bike. #1,2 and 3 was a little bit lower due to the 6° angle. But the #4 was high as hell!

The only reason I can see, is there's a problem with the needle. They are all brand new, but there's something bad with the needle or the seat and it doesn't stop fuel to enter in the carb.

|1, 2 and 3 are like that on the bike


But #4 


Here's a small video of the bike running: https://vimeo.com/388836618

Once again I'll remove the carbs and have a look at the #4 

[X-Ray]

Oh bugger. so they are all new needles/seats from the kit obviously. One thing I do when I have the carbs apart is also polish the float pins with scotchbrite and wd40, just to make sure the floats are nice and free moving. This is a strange one. Maybe remove the #4 needle and seat and just bench test those components, put the needle in the seat and drop some fuel into it with very light pressure on the needle and see if it leaks.

[Pat Conlon]

Does the float...float?

[Sparky84]

Do you have the right needle and seat?

Gravity fed or
Fuel pump type..

And would this pose a problem?

[stou]

Yesterday afternoon I attacked the #4! I removed the needle and seat to make sure the o'ring was ok. It was ok but I found a bit of dirt inside the seat, maybe something in my new auxiliary tank. So I cleaned it carefuly, I installed a fuel filter on the line from the auxiliary tank. I tested the needle and seat alone, and it work fine. I also used another float to be sure the float is not the problem. I did a first bench test and it leaked. I lifted the tab a little bit more and did some test a few times. It finaly work fine when the tab was at 3.25mm. It's stange compared to the other carbs which are lower. Maybe the seat of this one is borred deeper than the other.

This morning I took the bike outside and tested it. No leak!!!

I will wait spring to do the carb sync, I don't want to do it now, it's too cold outside. Since the garage is in the house basement, I avoid to have the bike running in the garage. So now that the carburetor issues are fixed, I'll be back to my "project thread" !

Thanks for your help and comments guys!

[FJmonkey]

Just don't let any crappy gas sit in the carbs.