Throttle repair question

How to keep the Cessna 170 flying and airworthy.

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pdb
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Throttle repair question

Post by pdb »

7F68E6ED-8C3C-4570-9507-2CB68D2A5204.jpeg
My throttle is slipping so I unscrewed the friction lock and discovered that the nylon wedge washer is cracked. When I tighten the lock, the nylon washer simply distorts and slips.

When I tried to figure out who could supply a replacement I was totally skunked. I can’t determine either a part number or a supplier. Does anyone have a clue about where to source a replacement?

Thanks,
Pete Brown
Anchorage, Alaska
N4563C 1953 170B
http://farm3.staticflickr.com/2366/2527 ... 4e43_b.jpg
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daedaluscan
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Re: Throttle repair question

Post by daedaluscan »

I think I would be making that.
Charlie

1956 170B C-GDRG #27019
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Bruce Fenstermacher
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Re: Throttle repair question

Post by Bruce Fenstermacher »

I'm with Charlie on that. A nice little project for a lathe.
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Bruce Fenstermacher
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Re: Throttle repair question

Post by Bruce Fenstermacher »

I'm with Charlie on that. A nice little project for a lathe.
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GAHorn
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Re: Throttle repair question

Post by GAHorn »

I have taken plumbing “packing” (usually made these days of teflon but in “olden” times was made of jute)...and wound a few wraps around the shaft and it worked for many years on my 206. https://www.homedepot.com/p/DANCO-3-32- ... /203193512

If you take the “replace” route:

https://www.aircraftspruce.com/catalog/ ... kkey=12964
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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n2582d
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Re: Throttle repair question

Post by n2582d »

George,
To replace the entire cable when the only problem is a friction packing is like buying new shoes when a shoelace breaks. But in looking at your recommended throttle I see that while the price looks good it is not a PMA'ed product. While it's tempting -- compare the price of your suggested cable to an FAA-approved one from McFarlane,-- I'd advise against going cheap. Earlier this month I was talking to a guy at our EAA chapter meeting. He related a story to me about having to deadstick his experimental onto a short grass strip built on the side of a hill nearby. His throttle cable had failed leaving him with only idle power. It's a long walk to civilization out in Pete's neck of the woods. A middle ground -- at least price-wise-- would be to buy Aircraft Spruce's FAA-Approved A-800 throttle cable. Their Part# 05-03866-1 (MFR Model# A-800-12-1), while not approved for the C-170B, is approved for the early model C-172. Both the 1953 C-170B and the early C-172 share the same throttle cable p/n 0411091-9.

Pete,
I wonder if McFarlane's EC12SK or EC312SK friction packings would work in place of the teflon. They have this page entitled "Extend the Life of Your McFarlane Throttle Cable" on their website. I think the original throttle cable was manufactured by Shakespeare. The friction lock material was rubber. Here's a clip from Service Letter 64-3:
Service Letter 64-3, Click to Enlarge
Service Letter 64-3, Click to Enlarge
Gary
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