Adding fuses

hotrod swinger

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I’ve recently posted about some electrical issues, notably my under dash wiring harness was melted together from the bulkhead connector to the ammeter. I’ve now repaired the harness and reinstalled it and, needless to say, I’d rather not have to do that again.

I have made the following mods to my 1973 Swinger factory wiring:

1. Ammeter bypass, wires are soldered together.
2. Bulkhead bypass, charging wire is 8 gauge with a 12 gauge fusible link.
3. Headlight relays.
4. Ignition relay.

If I understand things correctly, I have now eliminated most of the current going into the cabin, including battery charging current, headlight current, ignition circuit current, etc.

This leaves my heater blower, windshield wipers, radio, dash lights, brake lamps, turn signals, interior electric circuits, etc. The windshield wiper is protected by a circuit breaker built into the switch, and everything else is protected by the fuse box.

What remains completely unprotected from a short to ground are the wires that run from the alternator to the welded splice branching off to the ignition, headlight switch and fuse box. The wire from the starter relay lug is protected only by the factory fusible link.

I’m looking for opinions. Should I add a fusible link to the wire running from the alternator to the bulkhead connector? Or should I add inline fuses to both this wire and the wire from the starter lug to the bulkhead connector?
 

66 Valiant wagon

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If all the bulkhead connections are clean and the wiring in general is in good working order you're fine. You have a fusible link on the other end so there shouldn't be a need to splice in another on the alternator end.
Most of us aren't wiring experts and I sometimes think all these poor splices and connections cause people more harm then good.
 

67Dart273

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If you have your bypass charging wire fused, and have not eliminated the original factory fuse link, then the concern you mentioned should be protected "somewhat." The problem with that wiring, as original, is that the charge output and battery current through there makes it difficult to protect, simply because the original wire size is so small compared to the load

And old story: In the 70's my RR got banged up and I got a Valiant loaner, actually a second one, "after" this story
On a cold morning in San Diego, I was getting off "duty" at the RADAR shop, and hand gone out to start and warm the loaner. A 70's Val slant six. Few minutes later, our leading Chief came in and gave me the "detective Columbo" look. "Say Del, I just have one question. Is it supposed to be squealing and smoking?" So I went out there and the alternator was STOPPED. Turns out a diode had fallen out, and when I wiggled it, the thing SHORTED and I got to sit there and watch the ENTIRE ENGINE HARNESS smoke and fizzzle, after which----it blew the fuse link
 
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