creeping mixture and prop knobs

[Mooney13]

I am having a little "creeping" of my mixture and prop knob...mostly prop...Good news is I finally realized I am not losing my mind and the RPM was actually adjusting because of the knob....

Does anyone know of a fix for this, or do i need ot buy a bunch of stuff..?

Thanks!

[63M20C]

I have a 63C model, and when I purchased it, they were doing the same thing.  I was able to tighten then compression nut on the panel for the respective control a little, and it solved my problem. This was over two years ago and it is still working perfectly.

[mooniac58]

My prop control does this as well.  Creeps up in revs, especially when set 2450 or higher.  If set to 2500 it needs almost constant re-adjusting.

[N57039]

My mixture knob creeps rich. There is no compression nut. Very aggravating. Would love to here a solution from someone.

[Mooney13]

Hi Jim..if you run into that paperwork, I'm intereted..

Thanks!

 

[63M20C]

I guess I should have been more clear at what style I was using, though I am interested in replacing with the vernier style soon. Anyways, thanks for looking up the stc information.

[N57039]

Yes, my mixture control is a vernier style. The creeping is a new problem. From what I and my A/P can determine there is no way to tighten it up. Perhaps we're missing something.

[Mooney13]

I found someone with some experience dealing with creeping prop an mixture controls and they replied as follows:

"Take a piece out of an old leather belt. For size, unscrew the tightening knurl and cut a piece of belt just large enough to fit into the area behind the knurl nut so that when you re-tighten the large knurl nut it puts pressure on the shaft and that friction will stop mixture creep."

I am going to give it a try sometime this week (if weather works with me) and will keep you all posted.
If someone gets to it before me, please let us know how it works.

Thanks!

[Mooney13]

Well I gave it a shot today....and it worked as far as I can tell so far. I went for a flight and no more creeping.

Just be careful not to cut a piece that is too big. I did the first try and it was a real pain to get the leather out of the nut because it was jammed in there and you can’t really tell if you added too much until it is almost all the way tightened.

I ended up using pieces that were about 1/8 inch wide and 1/2 inch long...kind of wrapped them around the shafts.

Good luck!