carbs . Piston and needles

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Lorna c
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carbs . Piston and needles

Post by Lorna c »

hey quick question pls
why does one needle feel like it's too long now ? it's all the way up in the piston as far as it can go now and still snagging. if I pull back the plunger under the carbs so to make the hole lower , it'll make the tapping sound up and down . I push the copper tube that the fuel nut controls up and down(plunger) that the needle droppes into from the piston , if that goes up all the way it'll snag /stick . everything is back the same . paying attention to which one goes to which carb. . when the tube is out , I can feel the needle poking through at the bottom if the piston is in . it moves freely with out that in . or when it's down a bit . sticks pretty good with it all the way in /up .. I hope this makes sense to someone . I've been tinkering on this all day ..
:wink:
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Re: carbs . Piston and needles

Post by notoptoy »

I would check to make sure your needle is aligned and also make sure your needle is not bent. Is the base of the needle at least flush with the piston?
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Lorna c
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Re: carbs . Piston and needles

Post by Lorna c »

notoptoy wrote: Mon Jun 11, 2018 5:50 am I would check to make sure your needle is aligned and also make sure your needle is not bent. Is the base of the needle at least flush with the piston?
no . if the band is flush it's worse of a stick . it's like it grew .. I'll double check the straightness . . I spent some time straightening them . maybe something happened to one . also when I drop it in the back carb , it's fine . droppes in , clinks both ways . I've flipped parts in every possible way to make sure I didn't mix up parts . but seems to be fine until I drop it into the first carb . and only this one gives trouble..
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late 68 1600 3 main motor .
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Lorna c
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Re: carbs . Piston and needles

Post by Lorna c »

how to check if aligned ? but works in back carb nicely .. I'll check both those in the morning .. thx for something to look at . you can't _roll " those longer can you ? like during straightening of them ? just asking .lol. never know ..
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late 68 1600 3 main motor .
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Re: carbs . Piston and needles

Post by nismou20 »

Domes are numbered from factory to respective carb bodies too. Roll the needles on level surface to check for straightness and make sure the nozzle is centered in body. The bottom nut to body can be loosened to center nozzle.
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Re: carbs . Piston and needles

Post by Linda »

If the needle isn't straight you are wearing out the nozzle by rubbing. Check out nozzle prices . So I would advise new needles rather than trying to straighten .
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Lorna c
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Re: carbs . Piston and needles

Post by Lorna c »

nismou20 wrote: Mon Jun 11, 2018 11:51 am Domes are numbered from factory to respective carb bodies too. Roll the needles on level surface to check for straightness and make sure the nozzle is centered in body. The bottom nut to body can be loosened to center nozzle.
good to know ..
yes I took them apart and cleaned , straightened put back together . now this issue . it wasn't here before I took apart either .. this must be something I did obviously . I'm checking straitness now . not much movement . the nozzle must be what the needle goes into the bottom nut holds ? it's not loose , maybe bent ? I'll spin that in my drill too just to eliminate that .. .. report back . and Linda yes they're not something I want to wear ... I have 2 more sets of needles but I don't think they fit . when I drop into the nozzle , they don't seat to the ledge on them . they're for bigger holes I guess .. ?
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late 68 1600 3 main motor .
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Lorna c
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Re: carbs . Piston and needles

Post by Lorna c »

well everything was a touch bent . everything . I guess it didn't go back together exactly the same direction I took it apart or somebody said on it , but they had allot of movement in the drill . so straightened up and putting back now .
:wink:
"Is it me, or does everyone want to race ?"

late 68 1600 3 main motor .
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Lorna c
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Re: carbs . Piston and needles

Post by Lorna c »

also the nozzle wasn't centered . I didn't know it could be off a touch . well I get the great clanking sound off both carbs now . Carbs happy .. boy the cars loud not hooked up to a muffler . ..
:wink:
"Is it me, or does everyone want to race ?"

late 68 1600 3 main motor .
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