1. Hello Guest. You have limited privileges and you can't "SEARCH" the forums. Please "Log In" or "Sign Up" for additional functionality. Click HERE to proceed.

Wet setting the float levels

Discussion in 'XJ Technical Chat' started by quebecois59, Sep 28, 2015.

  1. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    Yesterday I levelled my carbs on my Workmate and started the wet setting procedure. Immediately I noticed a steady fuel leak from there:

    carbusXJ900.JPG

    Chacal and Hogfiddles confirmed that my fuel rail o-rings are leaking and that I will have to break the rack to replace them. I have to say that I was a bit upset, given the fact that they weren't leaking at all last fall when I took the carbs off of the bike.

    So today I was ready to order the parts I need, but I returned to the shed on re-opened the fuel valve and surprise! the fuel rails don't leak anymore ! It appears that the o-rings swelled back at their original dimension and make the seal.

    IS this common ?

    Anyhow it made me able to do the first step of the wet setting procedure. I found that #4 carb is way too high, actually it is less than 1 mm below the reference line, instead of 5 mm. Carb #3 is at 2.5 mm, better but not in specs. Carbs #1 and #2 are spot on 5 mm or very close. So , tell me if I'am right: with the carbs upside down, I will have to bend the tang up a bit to improve the situation of the carb float #3 ad #4, right?

    What kind od adjustment should I be looking for? Will I drop the fuel level 5 mm down if I bend the tang 1 mm up?
     
    Last edited: Sep 28, 2015
  2. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,093
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    think about it like this.
    if the floats are too high the tang it too far away from the needle and visa versa
    that way upside down or right side up doesn't matter
     
  3. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    So I have to bend the tang towards the float needle to lower the float level, right? Does a 1 mm difference on the tang makes a huge difference on the fuel level?
     
  4. k-moe

    k-moe Pie, Bacon, Bourbon. Moderator Premium Member

    Messages:
    19,613
    Likes Received:
    6,703
    Trophy Points:
    113
    Location:
    The City of Seven Hills
    Yes it does. You want to just barely bump the tang each time you go to adjust it.
     
  5. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    So it is like a trial-and-error procedure, nobody can tell by how much I should bend the tang to lower the level 5 mm?
     
  6. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,093
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    if a guy was really good with geometry he could figure it out but the poke and hope guy would be done by then.
    while you're doing this, don't scratch the area of the tang that slides on the needle pin. a divot there could cause the pin to hang up
     
  7. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    Thanks for the tip. I may give geometry a try before I go to bed.
     
  8. XJ550H

    XJ550H Well-Known Member Premium Member

    Messages:
    13,199
    Likes Received:
    3,854
    Trophy Points:
    113
    Location:
    Great North Woods
    he has the rule under the carb to do it
     
  9. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    I went back to the shed this morning and noticed a small fuel puddle on the floor under my carbs. I forgot to shut the fuel valve of my temporary fuel supply and carb #4 has flooded during the night and was dripping by the overflow. So there is more than an adjustment to be done on this one I guess. All float seats were very clean, and I put a fuel filter on my setup.

    When carb bowls were off, I noticed #4 carb float needle spring was operating like the others but looked noticeably weaker than the other ones when I performed what I'd call a bouncing test. Could it cause the carb to flood?

    I'll swap needles with carb #1 and see what happens.
     
  10. wizard

    wizard Active Member

    Messages:
    5,282
    Likes Received:
    26
    Trophy Points:
    38
    Location:
    DEVON ENGLAND
    Lift the float manually make sure it's shutting off. Sometimes a rap with the handle of a screwdriver will stop the flooding, of course, when the motor is running the vibration does that anyhow.
     
  11. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    I'll give it a try. If the flaot seems to shut normally I'll try swapping with #1 carb.
     
  12. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    The float operated very smoothly when pushed up manually so I drained and removed the bowls and measured the float height with the carbs upside down. All carbs #1, #2 and #3 are around 19.2 mm but #4 stands at 17.7 mm, which is a BIG difference. All tangs seem to be equally bent but I,ll try to measure the space accurately with my valve clearance gauges, at least on carbs #1 and #4 that area bit more easily accessible.
     
  13. XJ550H

    XJ550H Well-Known Member Premium Member

    Messages:
    13,199
    Likes Received:
    3,854
    Trophy Points:
    113
    Location:
    Great North Woods
    yes spring can be a prolem, do you have rubber tipped valves?
     
  14. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    No, metal tips.
     
  15. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    Well I think I got the picture: carbs #1 and #2 tang "openings" are about the same around 0.013 inch. Tang #3 is around 0.016 inch and #4 is around 0.019 inch !!

    What it says to me is that even if the tang is more bent on #4 float, it is not enough to push the needle up to shut the fuel supply. It also suggests that someone has already tried in the past to compensate the weak needle spring by prying the tang more opened., but it doesn't work anymore.

    I think it's time to order a new needle. The question is: should I order a new seat to fit the new needle?
     
  16. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,093
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    you should really get the needle and seat as a set
     
  17. tabaka45

    tabaka45 Well-Known Member

    Messages:
    2,348
    Likes Received:
    494
    Trophy Points:
    83
    Location:
    Brunswick, Georgia
    I would order a complete set of needles and seats. Chacal convinced me to use the solid brass needles and I've had zero problems with them. Also, I use a very small screwdriver to adjust the tang. I found needle nose pliers hard to deal with, especially when making the final adjustments.
     
  18. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    Solid brass needles is what I already have. Three of them work properly , so I don't see any reason to buy 4 needles and 4 seats for the moment.
     
  19. Polock

    Polock Well-Known Member

    Messages:
    9,751
    Likes Received:
    2,093
    Trophy Points:
    113
    Location:
    Beaver Falls, PA
    did you clean up the seats at all? i take a bit of #0000 steel wool on the end of a q-tip and spin that around in there till it's nice and shiney in there, then a drop of chrome cleaner on a fresh q-tip and spin that a minute, now clean it up and drop the needle in there and give it a spin or two and you should see a line on both pieces where they seated. now they shouldn't leak
     
  20. quebecois59

    quebecois59 Well-Known Member

    Messages:
    2,285
    Likes Received:
    112
    Trophy Points:
    63
    Location:
    Waterloo, Quebec, Canada
    Yes, but differently: I put the bottom part of a wooden golf tee in my drill , squeeze a bit of Aerosol (chrome cleaner) on the tip pf the tee and spin it in the float valve seat for a few seconds.

    The little spring in this needle is really weaker than the other ones. With the carbs upside down and bowls removed, if I give a little tap on it, the float in the other carbs bounces more than four times, but only twice with this one. The measuremetns I took of the height says a lot too: even with the tang bent the most, the float stands a lot lower.

    Maybe a could try bending the tang even more and see if I can make it close or not.
     

Share This Page