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Small burn on wire harness

Extra Fubar ยท 2020-11-07 08:28

Hi, I've tried to replace the battery of my 2008 CAT 305CCR this morning with a non-OEM one. I had little room and while installing it, the positive terminal touched one of the metal strap cable and there was some sparks, melting a bit the rubber cap and the the main wire harness (295-6475). Since some wires of the main wire harness are now exposed, I think I will have to replace it (about 1200 CAD$) :-( Should I check for anything else? Thanks,

Replies24
  1. #1Extra Fubar2020-11-07 08:43

    Also before replacing the whole harness, I think I'll remove the protective cable cover where it burn and try to replace the damage wires on a 6" span. Might be worth the try than replacing the whole thing.

  2. #2funwithfuel2020-11-07 09:02

    Can you attach a pic. From your description, I can't tell if you burned the convoluted tubing, nylon mesh or the actual wire insulation itself.

  3. #3Extra Fubar2020-11-07 17:08

    It did burn up to the wire itself... looks like two will need to be repaired.

  4. #4Extra Fubar2020-11-07 17:09

    Also, it looks like when I removed the battery the small positive/red wire snapped from somewhere. I have no clue where it is supposed to be connected. Any advice? See attached pic. Thanks!

  5. #5Delmer2020-11-07 17:42

    I'd strip that harness back and wrap it up, but DON'T FORGET in case it causes problems down the road. No help on the red one, but it can't reach too far. This is why you ALWAYS disconnect the ground first, and re connect the ground LAST.

  6. #6Extra Fubar2020-11-07 17:50

    Thanks Delmer - I was thinking about cutting the part where the wire insulation burn, soldering a new wire and using a shrink tube to insulate everything back. An other option was to use a female bullet and shrink tube after. What do you think?

  7. #7funwithfuel2020-11-07 18:36

    I'd stay away from solder or shrinky-dinks. They tend to cause breakage further down the line from vibration. As Delmer said, cut the insulation back a couple inches in each direction, separate the wires and tape tightly. Try and source 3M super 77 . It stretches nicely, tapes tight and adheres well. The stray hot wire most likely fed the cab power fuse or the alternator feed. I would look for a mega- maxi- or slo-blo fuse in that general area. Not a Cat guy, so can't answer definitively. Good luck.

  8. #8Jonas3022020-11-07 18:43

    Razorblade it back to get some room leave those wires connected use a tab of 3m electric sealant tape over them it sticks to itself and forms a gooy protection over the wire make sure to really sqeeze it around there and tape it all back up The littel red wire I would be looking for the alternator stud or a main fuse box that it hooked to

  9. #9kshansen2020-11-07 19:01

    I believe this is the tape Jonas302 is referring to: https://www.3m.com/3M/en_US/company...Splicing-Tape-23/?N=5002385+3294318588&rt=rud If you work with or know any good electricians, especially ones that work on commercial wiring like factories more so than just houses, they would have some! If you could include a S/N for the machine I might be able to see if SIS has a wiring diagram that might help with the short broken wire. But if it's that short I'd be looking for something real close! And next time you are working on battery cables disconnect the negative/grounding wire from the battery first and cover it so it can not touch the battery terminal. Then you won't be having this problem again! And the last wire to reconnect should be that negative wire at the battery!

  10. #10Billrog2020-11-07 20:56

    Liquid tape works very well for insulating wires.

  11. #11Welder Dave2020-11-08 00:35

    Ford makes special connectors and tape specifically for repairing wiring harnesses. It uses a special crimping tool. My mechanic friend used it to report a bad wire on my Cat harness. Cat or an auto electric shop may have something similar.

  12. #12mg23612020-11-08 05:40

    That tape is at Home Depot or Lowes for <$3

  13. #13Extra Fubar2020-11-08 07:05

    Wow, so many good answers. Many thanks to you all of you. I'll look for the 3M tape tomorrow at a local distributor for electricians here. I'll also try to see where goes that small red wire - alternator or fuse leading to it. Thanks!

  14. #14Extra Fubar2020-11-08 07:30

    @kshansen Thanks! Here's the S/N of my machine: HWJ03046

  15. #15Extra Fubar2020-11-08 09:18

    More fear than damages it seems...

  16. #16Extra Fubar2020-11-08 09:23

    I have attached a few pictures - one of the fuse box and one for a bus bar it seems. Looks like the top fuse box has only 2 wires going in while the bottom has 3. It looks like there's a left-over connector in that fuse box. What do you guys think?

  17. #17kshansen2020-11-08 14:13

    I believe that short red wire goes to a terminal block near the battery, look in the picture at item #49. It's not real clear in the drawing but if you go to the wiring diagram, also attached and trace out the wires from the battery you will find one red wire going from the + terminal on the battery over to the starter solenoid and the other wire goes to #49 terminal strip. #11 in this picture is the negative cable at the battery so that gives an idea where the terminal strip is located!

  18. #18Extra Fubar2020-11-08 15:32

    Hi @kshansen - many thanks for your response, it is much appreciated. I've cleaned a bit the area and attached a new picture. From my picture, I think I should attach it to #47, is that right? #49 seems like a bold to hold the busbar. What do you think about #47?

  19. #19Extra Fubar2020-11-08 15:44

    Hah! Ok I removed the #47 bold and the remains of the connector fell off, so it looks like it really is #47 BTW in the pic I uploaded, the top arrow points to #49. The bottom arrow points to #47.

  20. #20Bls repair2020-11-08 19:17

    Fusible links?

  21. #21Extra Fubar2020-11-13 12:36

    I got 3M Temflex 2155 tape to do the repairs on the burnt wires. Hopefully that will do it.

  22. #22Extra Fubar2020-11-14 17:58

    Quick follow-up on this - I did the repair today and all is fine. Nothing was damaged. Many thanks to all of you!

  23. #23kshansen2020-11-14 19:01

    Glad to hear it's working again. Be sure to save that wiring diagram I'm sure it will come in handy some day. I might even be tempted if it was my machine to take that file to some office supply shop that does custom printing and see what it would cost to get a large version of it printed something like poster size or even bigger. I know my 70+ year old eyes would like it. Also I think you will find that depending on the software you view it with you can do a search for a number off one wire and it will walk you through each and every place that wire is connected. Like X782 that has something to do with swing solenoid, lets you see every plug connector that one wire is connected to, if you need help on doing that type of search let me know.

  24. #24Extra Fubar2020-11-15 06:48

    Hi @kshansen - thanks for your reply. I'll indeed keep that PDF file handy and most likely print it. Again, thanks for everything!