The International Cessna 170 Association

My cables work perfectly they just look very bad.
Original cables with vinyl coating that has aged and turned yellow. I want "New" appearance.

My IPC from Sept 1 1956 is not much help.

Pg 116 Figure 70 index number 31 does not depict my install.

My contactor works perfectly but it is a plastic box that has aged.

C170B s.n. 26433 -

Can I purchase new cables just for appearance or do I try to recover cables

Suggestions appreciated.

Grady, the battery cables on my plane when I bought it a few years ago appeared to be original. They were covered by a white woven material/cloth further covered by a loose clear plastic sheath which had significantly yellowed. If you are talking about the same type of cables, I doubt anyone ever replaces just the clear plastic sheath. My guess is, everyone just replaces the entire cable. That's what I did. Although mine worked fine, they looked very old (not in a vintage way) and more importantly, had broken strands at the terminals. So it was time to replace them. You should carefully check yours for broken strands as well. If I remember correctly, the terminals were soldered onto those cables, which can embrittle the strands at the terminals and lead to breakage (along with age and use). If you find any broken strands, just replace the cables and be done with it. (Edit: I just checked the original cables that I removed (I kept them), and they were crimped not soldered. But you still need to check cables with crimped terminals for broken strands as its common for strands to break at the terminals.)

While Fig 70 on p. 116 of the IPC identifies Cessna part numbers for battery cables, I doubt they are available. I didn't bother to check. Again, I think the common practice is to make them up or buy them from someone like Bogert. In my opinion, Bogart's cables are rediculously expensive at something like $220 a set from A/C Spruce for a 170B, when you (or perhaps more appropriately your A&P) can make them up for far less. And I think you get a better product when you do it yourself because you can cut the cable to the exact length you need and orient/rotate the terminals so you don't need to twist the cable when installing it.

For your year model, Fig 72 on pp. 120-121 of the IPC provides more details about your battery cables (see wire numbers 2 and 3). The IPC shows the cables as being #4 gauge, but its pretty common on small Cessna singles to use thicker #2 gauge for better performance, reliability and safety margins. (If I remember correctly, Bogert uses even thicker #1 gauge for its cables.) If you make your own cables, it's now common practice to crimp the terminals (although some solder them). If you don't have access to an appropriate crimper for the gauge of your cables, you can buy a hydraulic one online (e.g. from Amazon) for about $40 that makes a nice strong hex crimp - and still be ahead of the game compared to buying ready-made cables. See this thread for more details.
http://cessna170.org/forums/viewtopic.p ... le+crimper

Of course, making battery cables is not preventive maintenance, so you need to do it under the supervision of your A&P.

gfeher
Thank you for sharing.

What type cables did you use? Can I purchase by the foot? Source of cable and terminals ?

Owned the IPC for 30 years, your reference to fig 72 pg 120-121 was revealing.

No problem Grady.

Aircraft Spruce sells 4 gauge MIL-W-22759/16 wire for $3.99/ft. If you want to go up to 2 gauge it's $4.90/ft. http://www.aircraftspruce.com/catalog/e ... dlwire.php

Spruce also sells Amp crimp ring terminals for those gauges at less than $2 a piece. http://www.aircraftspruce.com/pages/el/ ... tterms.php

While not strictly necessary, i think it's good practice to use heat shrink tubing at the transitions between the terminals and the cable. Spruce sells it for less than $3 for a 4 ft section (more than enough). http://www.aircraftspruce.com/catalog/e ... kkey=12231 But for battery cables, I like to use a thicker heat shrink tubing sold by NAPA. I can't tell which one it is online. But if you go to a NAPA store, you should find it. It's thicker than standard heat shrink tubing.

If you also want to replace your ground strap from your negative battery terminal to the firewall, NAPA sells them. I think this is the correct one, but you'll need to double check: https://www.napaonline.com/en/p/GRO849559 Or you can just replace your ground strap with a cable using the same wire gauge as on the positive side.

I'm not necessarily promoting Aircraft Spruce. It's just that I could quicky find links to the items there. You can find comparable items from other suppliers.

gefher

Thank you again for sharing

I purchased #2 gage WHITE cables from Spruce; did not want Red/Black from local auto supply. Try to avoid auto parts on airplanes.

Noted that fig 72 (wire number 2 , 3 ) list a 10 inch and 14 inch length cable.

What AMP terminal did you end up crimping ? AS list three (3) different stud sizes.

Plan is for A&P IA to assemble, install and logbook.

Grady, the table for Fig 72 actually indicates the terminal sizes for wires 2 and 3, though not directly. It identifies Sta-kon F71 terminals, which are 1/4" ring connectors, for the master solenoid ends, and F73, which are 3/8" ring connectors, for the battery and starter ends. So, if you have the original box-type master solenoid/contactor, 1/4" and 3/8" are the sizes you will need. If you have a different master solenoid, you will probably need terminals larger than 1/4 for those connections.

For the length of the cables, I suggest that you NOT use the lengths in the IPC, but rather measure the old cables that you are replacing and use those lengths. For example, for the serial number of my plane, the IPC says the cable from the positive battery terminal to the master solenoid is 10". But on my plane, the original cable was 11 1/2" and 10" would have been too short. So I made mine 11 1/2" and it fit perfectly. Same for the cable from the master solenoid to the starter. The IPC length was off by 1" for my plane. Bottom line: don't go by what's in the IPC or on anyone else's plane. Measure your old ones that fit and duplicate them. I'm guessing that your A&P will know this.

When you're making the cables, bend the wire to shape before crimping the terminals, otherwise they'll be hard to bend and keep bent. On a thick cable, the strands on the outside of a bend need to be longer than those on the inside, so you want them to slide against each other before crimping them in place.

DaveF wrote:When you're making the cables, bend the wire to shape before crimping the terminals, otherwise they'll be hard to bend and keep bent. On a thick cable, the strands on the outside of a bend need to be longer than those on the inside, so you want them to slide against each other before crimping them in place.

Good point. I would also make sure you pay attention to which way you align the terminals as the thick cables are not only are hard to bend but also hard to twist to align with the connecting lug.