Surprise Crack found

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b61652
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Surprise Crack found

Post by b61652 »

I am working on rigging my Cessna and replaced my yoke u-joints and while inspecting everything I noticed a grove and the closer I looked it started looking like a crack length wise on the tube that connects the cable and chains to the yoke. My suggestion is that every one check this in your aircraft. Looked like a defect from the factory or how it was fabricated. Not sure it is in a place to check every year due to the location. Across the top of the rod hidden by the chain lying over the tube. Should not have the stress on the part to cause this to crack. Pictures attached.
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rominoff
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Re: Surprise Crack found

Post by rominoff »

At first glance it does not look like a crack -very straight. that said, i've not looked at mine, will stick my head up there tomorrow. Now curious. Looked at one posted on ebay, looks (appears) to have the same lengthwise grove.
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b61652
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Re: Surprise Crack found

Post by b61652 »

Mine is definitely a crack or split. It ends about half the length of the rod. I will attach the end pic. This rod seems to be fairly thick and does not look like a rolled part from creation. Not sure if the crack would ever cause an issue with causing any flexing. I would be concerned if the crack started on the nut end/ adjustment end where the bolt appears to be pressed in. I have ordered a new/used one from a 172/182 as they seem to be the same part number and measured the same. I will keep the forum posted on replacement.
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2066
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Re: Surprise Crack found

Post by 2066 »

In any event, good eye! It's so easy to get complacent and "see" only what we're used to seeing. Thanks for sharing and for keeping us posted as you work through it.

Mac
rominoff
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Re: Surprise Crack found

Post by rominoff »

Looked at mine today -no split or crack, nothing to catch my fingernail on. Good Catch!
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6643
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Re: Surprise Crack found

Post by 6643 »

Since it's perfectly straight then it's probably the seam from forming the tube that has failed. It's puzzling, though, as there is normally very little force on that part. All it does is prevent the two yokes from being rotated in opposite directions.
8342
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Re: Surprise Crack found

Post by 8342 »

6643 wrote: Wed May 10, 2023 2:11 pm Since it's perfectly straight then it's probably the seam from forming the tube that has failed. It's puzzling, though, as there is normally very little force on that part. All it does is prevent the two yokes from being rotated in opposite directions.
When I was into mine I found the same thing. It looked like a natural seam to me and no real stresses on it to cause contol failure, so I left as is.

Rick
b61652
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Re: Surprise Crack found

Post by b61652 »

I have replaced it with a used one that has no cracks from BAS. Just as a reference looks like this is the same part on the 150-182 Cessnas From the looks of the new used one mine was defiantly a crack and not a seam. Would recommend everyone at least during annual to check theirs. Not sure there is any stress on this part but one end is pressed in or spot welded in my concern would be if the crack would widen it could cause the pressed in fitting to become loose or come apart during flight. It is not a really hard part to change and should not be ignored.
V529
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Re: Surprise Crack found

Post by V529 »

Well, something new. Thank you for finding and posting that defect. I've got a couple in the hangar and one on the airplane, I will look at them over the weekend. Now I've gotta crawl under that panel ..........again....... :roll:
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