How to adjust throttle valve screws on FCR 39 slant

2 replies to this topic
  • Dudemeister

Posted June 17, 2010 - 05:42 AM


So, I first tighten no. 1 and 2 - no problems.
Then I tighten no. 3 - and the throttle valve won't go up and down smoothly anymore (or not at all) :thumbsup:

How should I adjust the screws?

Also, I believe no. 3 should be more to the right (at the center), but I cannot get the rotating arm (in which screws 1 and 2 are screwed in to) further into the carb body...?

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  • grayracer513

Posted June 17, 2010 - 06:42 AM


The reason it binds up with all the screws tight is because there is something wrong with the link arm that runs between the shaft and the slide. It is likely bent or distorted so that when tightened, it binds on the slide.

As to why the shaft won't center up, I not certain that's critical, but if you can't move it by loosening screw 3, then you may have to completely disassemble the linkage to find the cause.

  • Dudemeister

Posted June 21, 2010 - 12:56 AM


I believe you are right - thanks!

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