Secret to adjusting throttle/mixture cables

[Scott Will]

OK... there has to be a secret.

Trying to set up my mixture cable on my IO-360 (Precision servo) with a center mounted throttle quadrant. What's frustrating is that it seems like I have too much movement in the cable... any adjustments make it worse on the other end of the spectrum.

I come from the RC world so setting up pushrods and what not should be second nature. What I might resort to is drilling another hole in the control arm of the mixture control (less movement in the cable required). Anyone done this?

Then there's the issue of securing the cables at the quadrant. Then seem to want to come down into the quadrant at an angle for best performance. Is this true?

Anyway, it seems like I'm wasting a lot of time on something that should be trivial!

[N79PT]

Scott,
-My Ellison TBI "carburetor" required more cable throw than my center quadrant could put out, so I drilled another hole. Works great. When you measure, better to have a little extra throw, than not enough.
-For maximum efficiency, the cable and lever arm should be 90 degrees at mid travel (quadrant and mixture arm) position. Makes sense?? Also you don't want to approach an over-center condition at cable extreme positions.
Good Luck.

[mark manda]

It took me several hours. I opted NOT to drill and barely clear the airbox. (in the idle cut off position)

I actually didn't have full idle mixture cut off, so I started all over with a mechanic friend to get it right.

And, then the throttle length, mine seems a bit too short.

good luck.

[RV7Guy]

Hi Scott,

Like RC the geometery has to be right. On my Throttle and mixture, I found the center of the travel of the cable then set the arm to that center and adjusted from there. Don't remember which one but I had to remove the arm and reposition. From there it was just tinkering.

[painless]

Anyway, it seems like I'm wasting a lot of time on something that should be trivial!

Boy, do I wish I had a nickle for every time I've said that!!

[dan]

Originally Posted by Scott Will

What I might resort to is drilling another hole in the control arm of the mixture control (less movement in the cable required). Anyone done this?

Yes, did this on my throttle & mixture arms on my AFP FM-200 injection servo. Needed that little bit extra throw for the same cable range.

I consider it a sub-ideal solution but a solution nonetheless!