Fuel screw?


7 replies to this topic
  • shoboat90

Posted April 10, 2007 - 11:30 AM

#1

Please forgive the ignorance.......but is the fuel screw the same as the pilot screw? My '02 426 seems to be backfiring quite a bit and I read a good thread on adjusting the fuel screw to possibly alleviate this.......but I can't find the screw? Can someone either post a pic or describe the location......the pic in the shop manual is very unclear to me.

thanks
jim

  • Ga426owner

Posted April 10, 2007 - 11:46 AM

#2

Do yourself a big favor and buy a adjustable fuel screw from ZipTy $19.00- it will make your life of adjusting so much easier. The stock fuel screw is recessed in the bottom of the carb bowl and almost impossible to adjust evenly. Remove it the spring and oring when swapping over to the adjustable fuel screw - Thre oring and spring get relocated on the new fuel screw. It is lower than the carb bowl and easy to adjust:thumbsup:

  • KJ790

Posted April 10, 2007 - 11:49 AM

#3

It is the same as the pilot screw in that it is a low adjuster. You have to turn it the opposite way from what you would turn an air screw on a two stroke though. Turn the fuel screw in to make it leaner and out to make it richer. The fuel screw is up in a hole on the bottom of the carb kinda behind the head of the drain bolt on the bottom of the float bowl. It is hard to get to unless you have a screwdriver that is the perfect size. Buy an aftermarket fuel screw that extends down so you can turn it with your fingers. They are well worth the 19 bucks.

  • grayracer513

Posted April 10, 2007 - 11:49 AM

#4

page 3-17 shows you where it's located. The view is of the left side of the carburetor float bowl. The screw itself is up in a well in the bowl between the front two bowl screws.

As just said, an after market extended screw makes things much simpler.

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  • shoboat90

Posted April 10, 2007 - 02:00 PM

#5

Thanks for the replies Gents. Am I correct to assume that I need to remove the carb in order to install the aftermarket fuel screw?

  • King_Air

Posted April 10, 2007 - 02:33 PM

#6

On my 00 426 I was able to loosen the air boots and rotate the carb far enough to replace the stock screw with an aftermarket. I had to remove the coil on the right side of the frame for the carb to rotate far enough. No need to remove the carb.

  • KJ790

Posted April 10, 2007 - 02:36 PM

#7

not if you have a screw driver that will fit up in the hole. If you can find a good screwdriver, just pull the old one out, switch over the spring, washer, and o-ring, put a little grease on the threads of the new fuel screw and put it in.

  • grayracer513

Posted April 10, 2007 - 02:37 PM

#8

No, you are not. Remove the screw from the bottom ( you may want to tilt the bottom of the carb outward) and put the new screw in its place. Note that there will be, from bottom to top of the stack, the screw, a spring, a washer, and an O-ring in the bore. The O-ring, and sometimes the washer, will frequently stick in the bore, and should be retrieved for inspection, and to account for all the parts.





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