1972 Engine Electrical

[jlampka]

Ref attached photos. So I am curious where to attach the red coiled 12 gage wire coming from the brake master cylinder area of the engine bay in the attached photo. It has a connector block like the block already attached to passenger fender by the battery - see next photo.

I recently bought this truck and have a few things to sort out. Any help appreciated. Thanks!

[notsolo]

Long red wire goes just on top of radiator in plastic pinch all the way across to alternator, on drivers side. Check in electrical section for schematic.

[LockDoc]

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That junction block is something someone has added. It is not stock.

LockDoc

[Coley]

As already stated...that second junction block with the nest of red wires is not stock.
It looks like someone has been working their way towards trying to run a new (full) 12 volt line to the ignition and then to the coil to the replace the stock/original lower voltage wire.

What type of distributor/ignition is in the truck? ie: stock (points?) with a separate coil?....or an HEI ignition?

All good
Coley

[VetteVet]

Did you have an auxiliary battery in the truck I.E. camper special that might have used these wires and junction? They are usually hot so check for voltage before connecting them to anything.
Like was said they are probably an additional power source for some device.

[jlampka]

Truck has options Z62 Custom Deluxe Equipment and UY1 Camper Wiring and there is no auxiliary battery so I bet it has something to do with the camper wiring option.

[68 P.O.S.]

A fusible link needs to be connected to the junction block as well. Don't remember off the top of my head what size tho.

[68 P.O.S.]

Here's an old thread that covers it pretty well. http://67-72chevytrucks.com/vboard/s...d.php?t=545962

[toolboxchev]

Originally Posted by VetteVet

Did you have an auxiliary battery in the truck I.E. camper special that might have used these wires and junction? They are usually hot so check for voltage before connecting them to anything.
Like was said they are probably an additional power source for some device.

No, not a Camper Special wiring, its a bit different...someone added that stuff in there for something. Wiring on these trucks is pretty easy once you trace stuff down.

The wiring schematics will show you everything for the most part, 99%, the rest is added on or changed for modified HEI or other accessories.