Tai Wheel Question

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friday
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Tai Wheel Question

Post by friday »

I am a new member with a newly purchased 1947 C140/85hp. I have a question about the tail wheel. It shimmies a lot and I am wondering if the springs are proper. Attached are pictures of the springs and tail wheel. The picture of the springs are with the weight off the tail wheel. Please let me know what you think.
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IMG_3526.jpg
IMG_3526.jpg (84.2 KiB) Viewed 1336 times
IMG_3506.jpg
IMG_3506.jpg (145.14 KiB) Viewed 1336 times
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6643
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Re: Tail Wheel Question

Post by 6643 »

I'm confused. It looks like two different planes with two different types of springs.

The second picture definitely shows the wrong springs.

Read the Neal Wright articles on tail wheel installations.

Technically, it appears the tailwheel shown in the second photo is not the right one, either, but it's not a safety of flight problem.
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6597
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Re: Tai Wheel Question

Post by 6597 »

Definitely 2 different tailwheel pics, note different tension springs.

Second pic has wrong tension springs and clearly too slack on the chains.

Angle on the tailwheel body in the second pic looks about right.

Definitely read Neal's article for starters.
friday
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Re: Tai Wheel Question

Post by friday »

All of you are correct. My mistake with the pics. The close up pic with the tail raised is the one in question. My apologies.
The springs appear to be to the early type, but do they look normal in the raised position with the gap between the springs?
I will try to get a picture of the correct aircraft and post it.
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6597
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Re: Tai Wheel Question

Post by 6597 »

The early 'main' spring is what we call a single bend. I think a lot of folks replace them every maybe 500 hours or so. The smaller springs can be reversed to get a little more life out of them. Offhand I'd say that 'main' spring needs replacing. A good time to replace the main mounting bolts/nuts.

Things to check regarding shimmy-tire pressure and the angle of the 3200 housing. Again, start with Neal's write up.
viewtopic.php?f=10&t=134

The retainer looks all wrong, that gizmo that wraps around the springs. It should look something like this.
parts57&58withspacer.JPG
parts57&58withspacer.JPG (52.53 KiB) Viewed 1231 times
Last edited by 6597 on Fri Oct 25, 2024 5:58 pm, edited 3 times in total.
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6643
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Re: Tai Wheel Question

Post by 6643 »

I thought you meant the steering springs, since you mentioned shimmy.

The main spring should be flat in the area where the gap is showing. I'm not sure if the different thickness leaves (maybe an illusion) are correct. As mentioned, the retainer is all wrong.

Read the Neal Wright articles, then go through the whole setup. The main leaf can be purchased separately. Stick with what you have; do not get one with the "double bend".
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6643
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Re: Tai Wheel Question

Post by 6643 »

Also, can you post a picture of your tailwheel, similar to the second picture above?
friday
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Re: Tai Wheel Question

Post by friday »

I am not located with the aircrft right now, but will try to get a picture of the complete tailwheel.
Also, is the a good source for the leaf spring retainer/clamp?
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Re: Tai Wheel Question

Post by 6597 »

friday
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Re: Tai Wheel Question

Post by friday »

Thanks for you all your help. I went with a new set of single bend leaf springs from Univair and it works great.
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