Mixture Control Stuck 1976 M20F

[Prestonalton]

So after landing and leaning the mixture for taxi I came to a stop and went through the shutdown checklist and I find that I can't move the mixture control at all. It is completely stuck. Somehow I was able to muscle it enough to idle cutoff but currently I'm grounded for the night in KBGE with a mixture control that won't budge an inch either rich or lean (it ended up being stuck exactly in the middle of it's travel) . Has anybody had this issue before? I have a 1976 M20F. I haven't had any signs of the mixture control being tough at all, it worked like a champ the entire flight and even leaning after landing. One thing we have ruled out is that the servo is not the issue, the lever moves fine, so it must be somewhere within the cable. Is it possible a cable could have seized up? Anyway, I'm stuck here until I can get home.

Thanks!

[carusoam]

Welcome aboard Preston...

That’s a tough one...

Cables that fail have been known to fail miserably in flight...

For your safety... consider how you want to handle this one seriously...

 

There are a few threads around here about how to purchase a new one...

Some threads about how to look for various types of failures, the cable frays and other unrecoverable things...

 

Become familiar with owner produced parts and a company called Macfarlane (sp?)

 

If not familiar, expect to use a mechanic to help you through the steps...

How Old is that cable, years and hours...?

Private pilot thoughts only, not a mechanic...

Good luck with your next steps...

Best regards,

-a-

[David_H]

What are the odds? Maybe I should buy a lottery ticket.

I just experienced a mixture seizure in a 75 M20F quadrant. It's been a real experience trying to get it sorted out.

[carusoam]

David,

Any word on the cause of failure?

OAT? Guess because it’s been really hot lately...

Best regards,

-a-

[David_H]

I had a mixture cable seize in the guide sleeve just before the fuel servo.

The mixture was leaned during the landing roll and could not be moved to idle cut off for the shutdown. It was a real sobering experience.

I'm currently working with Mcfarlane now and have one of their mixture cables sitting beside me (It's not correct.) It's not been a pleasant experience so far. It's not always as easy as ordering the correct part number.

Edited July 21, 2019 by David_H
Grammar

[carusoam]

Nothing scarier than stuck controls...

Best regards,

-a-

[David_H]

Was this a quadrant or push-pull control? 

[ELT]

Hi,

Similar happened to me.  I have a 1966 E with a push pull mixture.  The problem was NOT the cable or injector body.  It was a swivel connection attached to the end of the cable.  The socket that the swivel ball seats in was worn.  Tried to lubricate and it worked sometimes.  I would not fly it.  Also I happened to have the replacement swivel in my trove of spare parts.  Most shops will stock the part or can get tomorrow.  Check this it is easy to do.

Good Luck

Eddie 

[Yetti]

start with the simple stuff.   did you release the friction knob on the right side of the throttle quadrant?   That and then some triflow on the pivot points of things in the cockpit.    The last person I helped, found that the cable had slipped in the outer cable holder near the fuel servo.    check that too.

[Prestonalton]

7 hours ago, David_H said:

I had a mixture cable seize in the guide sleeve just before the fuel servo.

The mixture was leaned during the landing roll and could not be moved to idle cut off for the shutdown. It was a real sobering experience.

I'm currently working with Mcfarlane now and have one of their mixture cables sitting beside me (It's not correct.) It's not been a pleasant experience so far. It's not always as easy as ordering the correct part number.

This was exactly the same thing that happened to mine. It has the quadrant. Somehow I was able to get it to idle cutoff but it took quite a bit of muscle.

[Prestonalton]

One other idea that may be far fetched popped into my head. I recently had the plane in because the cowl flaps would not stay closed and had someone at my local FBO take a look at it. Just thinking about it, the Cowl Flap assembly is the exact location that the mixture cable runs out in the engine. Not sure if they bumped the cable or anything but it's odd that this happened shortly after maintenance in a similar location.

[Yetti]

They may have tightened the cable holder on the mixture just for good measure.