The 1947 - Present Chevrolet & GMC Truck Message Board Network - VetteVet

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)

- Electrical (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=64)

- - VetteVet - Wiring 2 for single battery diagram (https://67-72chevytrucks.com/vboard/showthread.php?t=737424)

VetteVet - Wiring 2 for single battery diagram

Re: VetteVet - Wiring 2 for single battery diagram

.............................

Quote:

Originally Posted by SilverMiner (Post 7937452)

VetteVet - hope you see this, as I have two questions about correctly performing the upgrades shown in the image you frequently share titled "Wiring 2 for single battery" (also attached below).

1st question - for the dark red sensing wire running from the distribution block to the alternator, is it correct to leave the original wiring in place and merely splice into the factory wire coming off the alternator? Or does the factory wire need to be eliminated entirely? What is the correct gauge for the new wire?

Well If you are going to use the new distribution block, or one similar to the one in the diagram, then you would want to get your sensing voltage from there, or from another junction where most of the electrical loads pick up their power. If I understand you correctly you wouldn't want to use the original factory wire.

Since it doesn't really carry any current supply, The sensing wire gauge doesn't need to be very large. I think anything from 16 to 12 gauge would work fine.

2nd question - Is there any harm in using 6 gauge wire from the starter solenoid to the distribution block instead of the 8 guage as shown? If using 6 gauge, should the fusible link then also be changed to 12 gauge?

This wire is the battery charge wire and the current supply when the engine is not running. You probably won't be using it for anything taxing the 8 gauge wires' current carrying abilities. It never hurts to go bigger on the wiring but it might be a little difficult to route it. The standard for a fusible link is 4 gauges smaller than the wire it protects. That would be a 10 gauge link.

It appears I might have slipped a couple extra side questions in, but we all greatly appreciate the excellent help you provide to this forum.

I don't mind, as I usually get a few extra questions in any thread, and I'm more than happy to try to answer them if I can. Most of the time other members will chime in with their own problems, and as long as they don't hijack the OPs thread, we will try to answer their questions as well.

Edited to add - I forgot to mention my truck is a 1980 K10 Suburban, 12SI v-belt style 100 amp PowerMaster alternator.

That should work well for you unless you intend to go to lowering bags with compressors or a huge wattage stereo amplifier.

Re: VetteVet - Wiring 2 for single battery diagram

Excellent, thanks so much for the response. I am following your diagram as faithfully as possible - I even bought the exact same junction block and am making the connections on the block in the order as shown in the diagram. Not sure if that makes any difference, but I find it satisfying to precisely follow well engineered plans. Only my j-block showed up black, dang it.

I will electrically isolate (but not completely remove) the original sensing wiring that ran back from the alternator along the valve cover to the junction in the factory harness and replace it with a 12ga. wire back to the junction block. That is what I assumed the diagram intended, but I thought it worthwhile to double check. There will still be factory systems such as the heater fan, dash lighting, power door locks and power rear window which will not be serviced through the new j-block, and I wasn't sure if those loads needed to be sensed by the alternator.

The loads distributed from the junction block will include minor draws such as supplementary charging points, aux. gauge lighting and other misc. systems in the cab off a relay triggered by key on. The major draws will be headlight and aux. LED light relays and a 250W stereo amplifier always hot off the j-block.