Amp to voltmeter wiring

[Justinp551]

I am wanting to swap the amp meter out for a volt meter. I have looked over the wiring diagrams and Atlantic z cars site and have used the search function but not finding my answers. So here they are

First. Removing the shunt. Am I correct to assume the two large wires get spliced together and tucked away? Remove the shunt from the engine bay.

Second. The two small wires for amp gauge will now be reused to be the charge light wire and volt wire. I got that far. Am I correct up to this point?

Now I know the L wire on the alt is the voltage feed to excite the field then once excited it only becomes live if the alt stops chaging hence the warning light.

My question is what wires connected/ connectors jump is need to go from the L connector through the harness through the small old amp wire to the charge light?

Next is the second amp wire. Where it would hook to the shunt, where would it go instead to give voltage appropriately. I know I could go straight to the battery + but I want to do it by properly integrating it into the harness. And to finish it off I do know I need to attach a new wire from the negative voltmeter term to a ground. I have studied the wiring diagrams but get lost before finding my answers. I am sure a few have figured it out. Thanks for the help

[jhm]

First off, I'm assuming that you still have the L6 motor in your car? I've done a V8 swap, so I can help with some of your questions; but not all.

 

First: yes, you're correct...the two large-gauge (12 gauge?) wires to the shunt can be spliced together and tucked away. Either of the two small wires can be used as voltage feed to your voltmeter. OR, you can pull your hot voltage (12+V) from some other source of your choice.

Second: where do you want to read your voltage from? The battery? Some point on the engine harness? The starter? Wherever you want to take your voltage reading from, is the answer to your question. I relocated my battery to the hatch, so I am taking my readings from a "hot post" in the engine compartment (services all my engine compartment 12V needs). You can even draw your hot voltage from one of the existing hot leads in the ammeter dash harness wiring (make sure it's hot only when the ignition is turned on).

Third: There's a ground lead in the Ammeter dash harness plug, which you can use to ground your voltmeter....or you can run a new ground wire to the voltmeter and ground it at the ground of your choice. I'm using the ground in the dash harness and it's working ok, but there's a lot of leads in that 40-year old dash harness that don't do what they're supposed to.

 

Hope this helps.

r/John