The International Cessna 170 Association

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

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.

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 work, thanks. I've been wondering how I'm going to save the knobs when my mixture and carb heat wires finally break!

Thanks for taking the time to photograph that repair. Years ago George Willford wrote up an alternative means of repair here.

Great example of an “owner produced part”.

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.

Looks like a good article for the 170 News.