Wet Set...Can Somebody Check My Work?

Ok...Carbs have been pulled, completely disassembled, dipped, rebuilt with new seals and o-rings, and bench sync'd.
So I built this contraption to hold the rack level in all directions while I filled the float bowl with gasoline:



These next two pictures are pretty representative of all four carbs:





The bottom of the "bubble" is just a shade below bottom of the carb body...suprisingly enough...all four were almost spot on the first time around...the dry set really helped.
So do I pass?

 

looks good depending on where it is supposed to be.
On my XJ1100 that would be a little high but it is really close.
Good Job!

 

You only pass if your fuel levels are all the same and in spec...
You need to know what your fuel levels need to be set at then measure them below the edge of the carb body like your doing. But you will need something to measure with. If you did measure with a proper gauge then you should be good. But if it's by eye then I would get a gauge or the carbs may have to come back off and this will need to be done again.

 

750 carbs are supposed to be set at 3mm +/- 1mm. The fuel level we're seeing is right at the edge of the carb body, which means it's way the hell high. The float tang needs to be bent up a wee bit to lower the fuel level in the bowl.

 

This illustration shows where the meniscus of the Fuel in the Clear Tube should be when you are within specs.

You need to be within the yellow or green.
Anything ABOVE the top of the Lock Washer if too High.

::: Float Height Limits ::: Yamaha Publications ::: Factory Manual :::


Green = Ideal
Yellow = Acceptable
Red (lower) = Fuel Starvation possible.
Red (higher) = Flooding possible.

 

There you have it. Granted, the angle of the photos may be throwing us off a tad, but they look high to me too. See Rick's diagram; personally I found the marked tube to be a PIA so I use a fine sharpie and put a precisely-measured mark on the carb bowls. Either method (graduated tube or a mark on the carbs) will work; but it's really hard to accurately "eyeball" 3mm to within 1mm either way.

This may help: http://www.xj4ever.com/setting%20fuel%20levels.pdf

 

So, there you have it....back to the lab!
Fitz....the pictures don't lie...I was under the, false, impression that the ideal float height was even with the carb body....not sure where I came up with that because I've read and reread as much as I could
Thanks to all that weighed in!
Will repost once carbs are readjusted.

 

So, there you have it....back to the lab!
Fitz....the pictures don't lie...I was under the, false, impression that the ideal float height was even with the carb body....not sure where I came up with that because I've read and reread as much as I could
Thanks to all that weighed in!
Will repost once carbs are readjusted.

 

RE: adjusting. Remember if you bend the tang enough to know you bent it you probably went too far. Think "nudge" or "tweak."

Also check the other little tab that forms the "downstop" for the float to ensure the floats don't go "over-center" and hang up when the bowls are empty.

 

that's about where mine are set, never found it to be a big deal......but, is that fuel line full? looks like a big bubble or somethings not right.
the bowls might not be full yet

 

Huh? where's the bubble? :?

 

Should be pretty accurate...I had "exercised" the float pins before I took pictures. (Fill/empty/run through/fill/empty/fill/check reading)
If the bubble you see is in the first/top picture, that was taken during my leak test...you can see that the petcock, in that picture, is closed.

 

third picture, is the fuel line full or empty

 

Third pic...fuel line is full...perhaps what you're seeing is the top of the "checker" line which has gone over the top of the carb rack and curled back around behind the main fuel line...perhaps that is the bubble you see...either way...I don't think there were any bubble during testing...
As always...your input is appreciated!

 

I probably would have toppled the carbs off the stack of cardboard boxes a few times with that set up. but hey, that's just me.

Is that a sew-up tire?

 

Same here actually lol :lol:

And well spotted, yes I believe there's a "tub" hanging to the right of the rack. All well and good til you go down a long hill & melt the glue! 8O

 

Ha ha...yes it is a sew-up (former bicycle mechanic here...I'm sometimes amazed how much '80's Japanese used cross engineering...so much is so similar...without the engine of course)

The carbs are not balanced on the boxes...I built this contraption...but the rubber reducer cannot handle the full weight of the carbs, so the boxes and miscellaneous hunks of metal are a kind of support structure as well as a leveling device...an engineer, I AM NOT!!