Carb Adjustment Husqvarna 350 Walbro 159 Carb (EPA) High Idling Problem Solved!

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Schoolteacher

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We successfully tuned my neighbors two 350's the idle allows the chain to come to a stop at idle.

But on my 1998 Husqvarna 350 I cannot get the low idle setting right.

The L screw is set at 1 -3/4 out, the H screw at 7/8 out, from all the way seated.
Saw start up cold just fine and restarts warm normal. What we've noticed is we can't seem to make any difference by turning the T screw either all the way in or all the way out, no change in rpms. Also if we turn the L idle screw further counterclockwise we can slow the idle until the chain stops, saw will idle in that position but bog out and have no power when you press the throttle.
We like the current settings on the saw and it starts good, runs good, good power all the way through the power band, just have the excessive high idle when off the throttle and after starting up. Any help is appreciated.
 
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Thanks Red Fir. Will pull the carb and have a look. Basically just over reving at idle, when I sit the saw on the ground with it running it idles but excessively high.

3:20 pm P.S.T.
Update: I pulled the carb again. Throttle plate screw was tight. Pulled the T screw and spring.
Reinstalled just tight enough that the spring will hold it in place and then a little bit more.
That should be just about the point when the pointed tip is just contacting the lever to open the throttle plate.
Then I pulled the L needle and disassembled the top and bottom covers and removed the gasket and rubber parts, sprayed the jet and the passage of the carb it screws into with carb cleaner.
Waiting now for any other information or ideas before reinstall and test run.
 
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Problem solved. Went back out to shop. Reassembled everything. I did not have the T screw with the conical end that pushes open the throttle plate adjusted far enough out. Fired up saw. Back to normal. Now we have three Husky 350's back in action, tuned up raring to go/
Fell a medium sized Red Alder, saw worked flawlessly.
 

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