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Cat 287b charging problems

ianjoub ยท 2018-06-22 11:07

My 287b is not charging. I replaced the alternator and both battery cables. I cleaned to electrical connections when I did that. The battery has good voltage and load tests good. Which wire in the 4 wire plug on the back of the alternator is the exciter wire (12v power/ trigger)? I want to test to see if the alt is being told to charge. Thanks in advance.

Replies12
  1. #1ianjoub2018-06-22 14:14

    Edit: 3 pin plug on the back of the alternator.

  2. #2heymccall2018-06-22 15:14

    Red...B+ Yellow... Ignition Green...idiot light (I think)

  3. #3ianjoub2018-06-22 15:23

    Thanks, will check and report back.

  4. #4ianjoub2018-06-22 16:26

    I should have looked more closely: I have 2 yellow and 1 green wires in that pigtail. One of the yellow wires has broken internally. I am trying to track down a new pigtail. I'll repair and report back. My guess is I bought an alternator and battery cables for nothing :shame:

  5. #5heymccall2018-06-22 17:02

    Similar to this plug

  6. #6Mark2502018-06-22 18:02

    hi guys are we talking the right alternator

  7. #7heymccall2018-06-22 18:11

    I dunno. He didn't give serial number, so I picked one.

  8. #8ianjoub2018-06-22 18:43

    1st pic is correct

  9. #9ianjoub2018-06-22 18:46

    You would think as long as I have been doing forums, I would include pertinent info like that, sorry.... Not by the machine to add that right now. Thanks again for all the help!

  10. #10Mark2502018-06-23 02:13

    wire 403 hour meter wire 308 power fro ignition switch wire c444 wire to indicator lamp group Mark

  11. #11ianjoub2018-06-23 18:43

    Thanks Mark.

  12. #12ianjoub2018-06-25 10:58

    Thanks again everyone. The power wire from the ignition was broken inside its rubber casing about 1/4 from the alternator plug. I jury rigged it for now and ordered the plug posted above. I am charging at 14.4v again.