Idle Adjustment Problem

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I have a Savage x 4.6 . When I try to adjust the idle setting to increase the idle speed it binds the slide valve. If I back it off a fraction the slide valve closes completely. When I go to break and it stalls. Is the adjustment screw damaged or is the carb toast.

 

[Alexander_0_1]

Your idle set screw controls how much your slide valve closes when off the throttle or when brakes are applied. Typically it should only be open .5-1mm when off the throttle or when on the brakes. To adjust how you engine idles you need to adjust the LSN (low speed needle) this must be done slowly in 1/12 turn increments, much like a clock face. Be sure to let your engine fully adjust to any changes you make by letting it idle. I'd say about 3-5mins. By the 5min mark you should be able to hear the difference in idle.

 

[[email protected]]

I know how to adjust it. The problem is there is no adjustment. At the point when it should be adjusting the idle when I tighten 1/12 turn it binds the slide valve. When I back off 1/12 turn the slide valve closes completely. I have no idle setting .

 

[Rolex]

The idle adjust needle comes to a point and that point MUST be in the groove of the barrel in order to function. That applies to slide and rotary carbs.
Loosen the idle screw enough to know that you can rotate the barrel when it's out of the groove. Slowly start to tighten the idle screw while rotating the carb barrel from side to side. When you feel a slight tension you'll know the tip of the screw is touching the barrel. By rotating from side to side you'll be able to feel it drop in. Tighten the screw a little more, and you will no longer be able to rotate the barrel from side to side.
You're in the groove. Now is the point where you can adjust your idle to the proper opening for your starting point.

 

[Cornholio]

+1 to what Rolex just stated, that should fix your problem.

 

[Nitro Nerd]

Just take it apart and reset it. I've had them come loose before or not fully seated. See attached pic. Reset the needles in the housing groove and that should fix the problem (or at least verify whether there is a problem).

Also, applying brakes should not move the throttle in so if you are seeing that (or it stalls as you noted) check your linkage.

Note: the carb in the picture below is not from a Savage engine...but the concept is the same. Let us know the results.

 

[[email protected]]

Thanks for the help. I took the carb apart and got the idle screw in the grove . It seems to be working properly now.