Cowl flap indicator attachment at the arm assembly

[shawnd]

Hello folks. I am looking for photos / guidance on how the cowl flap indicator cable should be properly attached to the cowl flap arm assembly controlled by the cowl flap motor. I am in the process of replacing that cable in my a/c 1986 M20K and the previous installation sure looked like it was jerry rigged.  As a result cowl flap indication was off. The IPC doesn't add any value to this matter but adding the picture for context. Thank you!

 

 

[N201MKTurbo]

Just take an AN3 bolt and drill a 1/16 inch hole in it. The hole should the thickness of the arm plus 3 thin washers from the head. It is easier to drill the hole with a 1/16 inch end mill. Put a thin washer on the bolt, push it through the arm, place another thin washer on the bolt. Push the wire through the hole, place another washer on the threads past the wire and finish off with a lock nut. Hold the bolt with a wrench and tighten the nut till it clamps the wire. Put a couple of drops of oil on it and you are done.

[Aerodon]

Macfarlane make a number of cable clamping bolts and accessories:

https://www.mcfarlaneaviation.com/products/product/MCS2323-6/

 

[shawnd]

Thank you @N201MKTurbo and @Aerodon Is this the factory way or an approved FAR Part 43 style application? Curious what the factory did - and its a bummer they do not have this documented properly in the IPC. There's no way it just sits in the clevis pin as shown in the diagram. But the clamping bolt style approach sounds like the right one. 

[N201MKTurbo]

55 minutes ago, shawnd said:

Thank you @N201MKTurbo and @Aerodon Is this the factory way or an approved FAR Part 43 style application? Curious what the factory did - and its a bummer they do not have this documented properly in the IPC. There's no way it just sits in the clevis pin as shown in the diagram. But the clamping bolt style approach sounds like the right one. 

That drawing shows a clevis pin with a hole in it. The only way that would work is to bend the wire around it. The bolt thing has been used forever. I think Mooney may have been cheaping out on this one.

What kind of jerry rigging did you have?

[Aerodon]

Shawn, I have not seen the cowl flap end, but will go look next week.  Here is my broken flap indicator end, I could not figure out how the wire was fastened to this post. 

I should have taken pictures of the trim indicator wire when it as opened up.  Next time.

 

Aerodon

 

[shawnd]

Here's what it was... the SS piano wire went through but along with it went a safety wire which was wrapped back around and then wrapped around the piano wire.

 

 

[N201MKTurbo]

That looks like the drawing. I guess they couldn’t afford cotter pins.