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Fuel mixture screw problem

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The 3x3 is done and jetting. JD kit

1000-800feet above sea

160 main

25 pilot

Mrd ssw not instaled yet. Still needs to be shipped so I just opend up the stock for now ( I know it isnt the same)

The directions say screw in the extended fuel mixture screw untill it is lightly seated. Well the screw is very easy to turn untill the last 2 turnes when it is going in( or lean). I can do it but it feals a little tite and kind of hard with my fingers.

Is this normal? Thanks again for all of your input

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What fuel screw do you have....is it aluminum or brass? Some of the aluminum screws are not a good fit and get loose and can even fall out. When you installed it did you feel it scraping the threads of the screw on the passageway as you slipped it....people have had problems with this since it damages the threads so they don't screw in properly. If the threads are buggered up its toast....I did it to mine once and had to put caulking sealant on it to keep it from falling out until I got a new fuel screw. It should screw in nice and smooth all the way yet have plenty of resistance to hold it in place once it is a turn and a half in or so. I now run a Merge fuel screw...brass and nicely threaded so it won't move once set. I have a feeling the threads are messed up and you are bottomed out and thats why it is hard to turn.....it should turn smoothly until it stops....only use light pressure once it bottoms out.....if its still loose you need a new one.

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It is a good screw it is stainless. Threads are fine just seams a little tite just befor it bottoms. And lets get the " did you cross thread the screw" part strait. As I said befor it screws in fine all the way untill the very end. If it was cross threaded it would be gradualy harder from the begining and be very hard to get backout, and there is a lot of threads to screw in before you get to the last 2 turns, so no its not cross threaded and there is nothing in the threads to jam it up.

I guess my question is; is the screw supposed to go in all the way to the point were the the bottom of the screw head is seated on the carb, or will there b a little gap between them?

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The screw is screwed in until it is lightly seated, ie, resistance. If you force it further, you crush the tiny oring and can damage the carb needle seat (just soft brass.)

Yes, there will be a gap between the screw head the botton of the float bowl.

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Whats the fix if you screwed up the threads? I can't get mine to screw all the way in...The fuel screw hangs out of the bottom of the float bowl. I haven't tried to start it yet.

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Whats the fix if you screwed up the threads? I can't get mine to screw all the way in...The fuel screw hangs out of the bottom of the float bowl. I haven't tried to start it yet.

If you have the extended screw it should stick out below the hole by 1/4 inch or so to make it accessible. Think of it as a permanently attached screwdriver to make it easy to turn the screw that is up inside the carb.

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