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Float adjustment?


slice
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Ok confession time, I have never adjusted the floats on any of my bikes ! and really have no idea how to do it, hunted around youtube and found a few peeps doing it and followed their instructions and found it fairly easy, you learn new stuff every day don't you? anyway my problem now is that the FJ carbs should be 22.3 mm from the lip of the float bowl but mine are a whopping great 30+mm so that explains the fuel leak !! but in the manual it says that the tang should not touch or compress the small plunger on the float needle, so how the hell am I supposed to bend the tang down without it hitting the plunger? I mean it's already pretty close but if I adjust the float up to get the right depth for the fuel level it has to hit the bloody plunger !! Some of you lads and lasses do this to your 2T bikes on a regular basis and was wondering if you might be able, in words of one syllable, to tell me what if anything I'm doing wrong, as at the moment I have the right float height but the wrong position on the needle valve, at least that is what the manual says. I can by the way strip down clean and replace the last nut bolt and washer on most carbs but this piece of info about float height has obviously gone right over my head. Thanks for any advice.

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Words of one silly bull? :lol:

Ask... this... on... the... F...J...O...C... Boards!!

Seriously, there are a couple of FJ-specific tools required for certain tasks. Valve shims being one of them.

There are certain ways to achieve this without the tool and without fucking up the bike, but it is very specific to the FJ.

Honestly, even I don't know this one, so I *really* would advise asking there. They'll know.

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Hold the carbs on a angle so the tang just barley touches the needle plunger,that way the float weight is not on the needle there by not compressing the needle plunger, and adjust the tang as nessary untill you get the right height.

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Hold the carbs on a angle so the tang just barley touches the needle plunger,that way the float weight is not on the needle there by not compressing the needle plunger, and adjust the tang as nessary untill you get the right height.

That's it+1

Dont see how it explains a fuel leak though, it will mean not enough fuel in the bowl...not too much fuel!

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Ya what air head said at 30mm the float would be closing the needle earlier leaving less fuel in the bowl,,must have worn seats/needles?

When does it leak fuel at rest? that woud be a bad petcock seal. Only 10 bucks or so to change

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NO sorry what I mean is that the float is 30 mm to low in the bowl so more fuel is getting in than it was designed for so hence the fuel leak out of the over flow on the carb, my problem as above is that with the tang bent down to the correct float, up position, I am hitting the needle to early and am going to have to little fuel if it's to low in the bowl. bloody difficult to explain really as it's not only upside down it's leaning away from me !!

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NO sorry what I mean is that the float is 30 mm to low in the bowl so more fuel is getting in than it was designed for so hence the fuel leak out of the over flow on the carb, my problem as above is that with the tang bent down to the correct float, up position, I am hitting the needle to early and am going to have to little fuel if it's to low in the bowl. bloody difficult to explain really as it's not only upside down it's leaning away from me !!

beats me slice, i dunno WTF you're on about mate :crazy:

Perhaps you're having troble making the mental switch of having the carb inverted...if the distance from the flange to the bottom of the float is greater than spec...then there will be too little fuel in the bowl...honest ;)

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Ok I will try againg hold carbs so float piviot pin is up and carbs are 90 deg from normal and slowly rotate the entire carb body with the piviot up till the tang just barley touches the plunger pin then take your measurement.

Typicaly the arm that hold the floats from piviot will now be level with the carb body where the bowl fits or just slightly raised at the far end of the pivot

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Ah I see dt, that is perfect sense, so if I lean the carb body away till the tang is off of the pin on the needle then measure the gap it should tell me the exact distance from the float bowl level. got it, I will try that and get back to you. Now I know why I never did this before! In the youtube vid the guy on there has adjusted the float on the level without tilting it forward till the tang is off of the pin, he was adjusting an xj600 set of carbs so I assumed (wrong!) that mine would be similar.

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it all depends on the strength of the spring loaded pin, some are so strong they will support the weight of the float without compressing the spring...however, most arent.

Incline the carb so that the tang just touches the pin, not "off the pin"...there will be no gap, it's touching the pin

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This is how I do it Slice. When the carb is upside down hold the float just off the pin with your finger and then measure. Then adjust until its the correct height.

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Oh Ok Preload never thought of that DOH! you start with doing it one way and forget that there are other ways of doing it, locked into it I suppose. going out there to do it today and will see what happens, this is a spare set for the FJ so I can afford to get it wrong, just for some reason I have never adjusted the floats before, suppose I thought that they were set at the factory and never needed doing. I thought that a lot of the T2 boys and girls did this on a regular basis for some reason?

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