Alternator wire repairs

Forum for both AC and DC electrical components. From engine alternator to dashboard, inverter to batteries, and everything electrical in-between.
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LionDriver
Posts: 15
Joined: Wed Jul 29, 2020 2:45 pm

Alternator wire repairs

Post by LionDriver »

Always do checks on your engine components, you may find something like this:
I was looking for the intake air heater wires for my instruments going out issue (see other thread) and I found one of the small top wires on the alternator was rubbing on a hose and completely exposed.
A0D12DA1-E771-4A98-A64A-B7579075A49A.jpeg
A0D12DA1-E771-4A98-A64A-B7579075A49A.jpeg (863.94 KiB) Viewed 3670 times
It was touching a metal pipe, smashed up against it, so may have been shorting. Also, the other top wire was lose in the connector and could easy slip off. So I replaced the wire, used contact cleaner and fixed the terminals. Anyone know what these wires are for? Interesting that the broken wire had a diode on it.
8610C9C4-62AE-4CF7-A79E-098D3C39D8D6.jpeg
8610C9C4-62AE-4CF7-A79E-098D3C39D8D6.jpeg (2.67 MiB) Viewed 3670 times
If you have to do any electrical work on your Safari, I highly suggest having a good terminal cleaning kit like this:
3E6A320D-5581-4050-94AB-0C71946D0EA5.jpeg
3E6A320D-5581-4050-94AB-0C71946D0EA5.jpeg (198.46 KiB) Viewed 3670 times
I still have to test the engine and see what happens, but I somewhat doubt this will fix my instrument fuse blowing issue.
96 Safari Serengeti 38’ Cat 3126
Tiger trax, safe-t plus, koni
LionDriver
Posts: 15
Joined: Wed Jul 29, 2020 2:45 pm

Re: Alternator wire repairs

Post by LionDriver »

Tested starting up the engine and it started and alternator is working fine. Using the silverleaf I watched as the batteries went from 13 volts to 13.6 volts. No other charger connected. Wont be able to know if the instrument guages fuse will blow until after I drive it in a couple days.
96 Safari Serengeti 38’ Cat 3126
Tiger trax, safe-t plus, koni
LionDriver
Posts: 15
Joined: Wed Jul 29, 2020 2:45 pm

Re: Alternator wire repairs

Post by LionDriver »

After researching those top terminals on the alternator, the one that was smashed and possibly shorted on mine was the battery sense wire, it senses for voltage drop over the positive cable and adjusts the alternator output to compensate. If it was indeed shorting, it was a major drain to ground from the battery. The diode in that circuit just keeps the alternator from feeding back power in that wire.

The other terminal seems to be some connection to the alternator light in the instruments. I've never seen a battery or alternator type light in my instrument warning lights and I still don't see one now when turning the key to acc. Will have to check for a broken bulb there.
alternator-wiring.jpg
alternator-wiring.jpg (68.91 KiB) Viewed 3658 times
96 Safari Serengeti 38’ Cat 3126
Tiger trax, safe-t plus, koni
stuplich@ymail.com
Posts: 1146
Joined: Mon Oct 28, 2019 8:51 am

Re: Alternator wire repairs

Post by stuplich@ymail.com »

LionDriver wrote: Fri Oct 09, 2020 9:42 am After researching those top terminals on the alternator, the one that was smashed and possibly shorted on mine was the battery sense wire, it senses for voltage drop over the positive cable and adjusts the alternator output to compensate. If it was indeed shorting, it was a major drain to ground from the battery. The diode in that circuit just keeps the alternator from feeding back power in that wire.
The other terminal seems to be some connection to the alternator light in the instruments. I've never seen a battery or alternator type light in my instrument warning lights and I still don't see one now when turning the key to acc. Will have to check for a broken bulb there.
Lion Driver
As built,(and wired), by SMC/Magnum the DelcoRemy alternator on my coach HAS NO KEY/ALT LIGHT WIRE ..(ONLY THE "Voltage Sense" wire) .. and NO "alternator type light" in the dash instrument warning lights.
Image
BTW a freind's '96 Serengeti is the same.
Mel
'96 Sahara 3530, mine since '01
250 hp 3126 Cat, MD3060 Allison
LionDriver
Posts: 15
Joined: Wed Jul 29, 2020 2:45 pm

Re: Alternator wire repairs

Post by LionDriver »

Well, whatever those two wires are, one of them fixed my instruments. Drove for a good half hour today and the gauges all worked. I will update the other thread with the info so anyone looking for help in the future finds it. Finally fixed the issue that has been plaguing me for well over a year.
96 Safari Serengeti 38’ Cat 3126
Tiger trax, safe-t plus, koni
stuplich@ymail.com
Posts: 1146
Joined: Mon Oct 28, 2019 8:51 am

Re: Alternator wire repairs

Post by stuplich@ymail.com »

LionDriver wrote: Sat Oct 10, 2020 8:03 pm Well, whatever those two wires are, one of them fixed my instruments. Drove for a good half hour today and the gauges all worked. I will update the other thread with the info so anyone looking for help in the future finds it. Finally fixed the issue that has been plaguing me for well over a year.
LionDriver
Other thread??
Mel
'96 Sahara 3530, mine since '01
250 hp 3126 Cat, MD3060 Allison
LionDriver
Posts: 15
Joined: Wed Jul 29, 2020 2:45 pm

Re: Alternator wire repairs

Post by LionDriver »

I haven’t updated it yet as I want to get more pictures, there is an older post(thread is forum speak) of mine here where I talk about the instruments going out issue, I didn’t think this was related so I made this post, it turns out it is related, so I will update the original post.
96 Safari Serengeti 38’ Cat 3126
Tiger trax, safe-t plus, koni
TDJohn
Posts: 552
Joined: Sun Oct 27, 2019 11:34 pm

Re: Alternator wire repairs

Post by TDJohn »

LionDriver wrote: Thu Oct 08, 2020 5:17 pm Always do checks on your engine components, you may find something like this:
I was looking for the intake air heater wires for my instruments going out issue (see other thread) and I found one of the small top wires on the alternator was rubbing on a hose and completely exposed.
A0D12DA1-E771-4A98-A64A-B7579075A49A.jpeg
It was touching a metal pipe, smashed up against it, so may have been shorting. Also, the other top wire was lose in the connector and could easy slip off. So I replaced the wire, used contact cleaner and fixed the terminals. Anyone know what these wires are for? Interesting that the broken wire had a diode on it.

8610C9C4-62AE-4CF7-A79E-098D3C39D8D6.jpeg

If you have to do any electrical work on your Safari, I highly suggest having a good terminal cleaning kit like this:

3E6A320D-5581-4050-94AB-0C71946D0EA5.jpeg

I still have to test the engine and see what happens, but I somewhat doubt this will fix my instrument fuse blowing issue.
Lion,

Looking at your second photo, it appears that your positive alternator output wire (black heavier gauge wire) has potential to rub against that same metal pipe. If that rubs through, it will short out the alternator. I would suggest installing some type of shield to protect that wire.

Glad to hear that your were able to resolve your problems.
John
'95 Serengeti, Cummins C8.3-300
Allison 6spd.
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