Mixture Cable Caution

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C170U2
Posts: 436
Joined: Sat Dec 22, 2012 4:30 am

Mixture Cable Caution

Post by C170U2 »

IMG_4541.JPG
Just wanted to give you guys a heads up what I found with my mixture cable. The end of the cable had split where it attaches to the carburetor. This was the original cable and survived 70 years. Glad I found it. It would be something good for you all to take a close look at during your next annual.

Fly safe! Mike
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n2582d
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Joined: Mon Apr 29, 2002 4:58 am

Re: Mixture Cable Caution

Post by n2582d »

Mike,
Thanks for sharing that. Quite impressive for that to be the original cable. I was looking at the IPC for the attach hardware for the mixture cable. The bolt called out for in C-170 IPC (fig. 34-46) calls for bolt p/n 0450311-2 and a AN365-428 nut. Standard practice these days calls for using all-metal stop nuts -- AN363-428 in this case rather than the AN365 nut with the nylon insert. I also noted that the C-170B IPC incorrectly shows the bolt here to be p/n 0350311-2 rather than the 0450311-2 bolt it calls for in the earlier model IPCs. If you're looking for that cable to last longer than 70 years you might consider installing McFarlane's MCS2323-2 bolt which has the hole chamfered to reduce stress on the cable. Finally, for those inspecting these cables, here's a discussion about clamps for bowden cables.
Gary
C170U2
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Joined: Sat Dec 22, 2012 4:30 am

Re: Mixture Cable Caution

Post by C170U2 »

I was hoping I could just go to my favorite salvage yard (Faeth Aircraft) and find a replacement cable......no luck. Those ugly salmon colored knobs seem to be like hens teeth. Here is how I repaired my old cable. I cut the wire off my old knob, drilled out the rod to accept the new wire I found at Faeths, added a dab of hysol, and crimped the end. Stronger than it was before and I get to maintain the look of the panel. I probably could have just purchased a new cable from Spruce and painted the knob but this worked for me. I also rounded to corners of my old bolt in similar fashion to the Mcfarlane bolt and ensured I had movement on the mixture arm. I then bent the extra wire around the bolt. Pretty happy with it.
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DaveF
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Re: Mixture Cable Caution

Post by DaveF »

Great work, thanks. I've been wondering how I'm going to save the knobs when my mixture and carb heat wires finally break!
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n2582d
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Re: Mixture Cable Caution

Post by n2582d »

Thanks for taking the time to photograph that repair. Years ago George Willford wrote up an alternative means of repair here.
Gary
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GAHorn
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Re: Mixture Cable Caution

Post by GAHorn »

Great example of an “owner produced part”. :D
'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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bsdunek
Posts: 425
Joined: Wed Feb 11, 2004 6:42 pm

Re: Mixture Cable Caution

Post by bsdunek »

C170U2 wrote:I was hoping I could just go to my favorite salvage yard (Faeth Aircraft) and find a replacement cable......no luck. Those ugly salmon colored knobs seem to be like hens teeth. Here is how I repaired my old cable. I cut the wire off my old knob, drilled out the rod to accept the new wire I found at Faeths, added a dab of hysol, and crimped the end. Stronger than it was before and I get to maintain the look of the panel. I probably could have just purchased a new cable from Spruce and painted the knob but this worked for me. I also rounded to corners of my old bolt in similar fashion to the Mcfarlane bolt and ensured I had movement on the mixture arm. I then bent the extra wire around the bolt. Pretty happy with it.
Great idea! Wondered what I was going to do when one of my cables fails. I am trying to keep my 170 as original looking a practical.
Bruce
1950 170A N5559C
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cessna170bdriver
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Joined: Mon Apr 22, 2002 5:13 pm

Re: Mixture Cable Caution

Post by cessna170bdriver »

Looks like a good article for the 170 News. :wink:
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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