New one wire alternator/voltmeter gauge question

[PeteJr]

My new engine came with a nice 140 amp 1 wire alternator.
The question is .......
Can I connect this to my stock voltmeter gauge?
I've read/been told 20 different answers.
Been told it will be OK.
Been told if you hook it up, it'll fry the new alternator.

If so, which wire is it and does it connect to one of the two remaining (now unused double plug terminals) on the alternator.

I ordered a wiring diagram for my year truck but it seems to be missing some pages.
I hate car electrical stuff and household plumbing !!

Thanks for any input, fellas.

 

[Ricko1966]

A voltmeter is not going to fry an alternator no way no how. I haven't looked for a wiring diaghram for your truck.Find a wiring diaghram,find the hot lead for your voltmeter hook it to a switched 12v source. I was going to try get you better info, but don't know what you are working on.

 

[Camar068]

A voltmeter is not going to fry an alternator no way no how. I haven't looked for a wiring diaghram for your truck.Find a wiring diaghram,find the hot lead for your voltmeter hook it to a switched 12v source. I was going to try get you better info, but don't know what you are working on.

agree, have heard some horror stories about amp gauges....don't recall the issue, but not with a volt gauge.

 

[75gmck25]

I don’t know who you have been talking to before, but they are all very confused. The dash gauge just measures voltage, not amperage. You need to use a larger gauge charge wire with the new alternator, but the stock voltmeter gauge will work fine.

With a 140 amp alternator I would want to use 8 or 6 gauge charge wire, and run it from the alternator bat terminal (the threaded post on the back) as directly as possible over to the battery positive terminal. Use a fusible link that is 4 gauge sizes bigger than the charge wire (e.g., use a 12 gauge fusible link with an 8 gauge wire), or use a high amperage holder.

These directions from Painless are for a 200 amp system with fuse holder, but you can use the same setup and just swap in a 140 amp fuse. https://www.painlessperformance.com/Manuals/30700.pdf

 

[PeteJr]

Rick, Davis, Br

I don’t know who you have been talking to before, but they are all very confused. The dash gauge just measures voltage, not amperage. You need to use a larger gauge charge wire with the new alternator, but the stock voltmeter gauge will work fine.

With a 140 amp alternator I would want to use 8 or 6 gauge charge wire, and run it from the alternator bat terminal (the threaded post on the back) as directly as possible over to the battery positive terminal. Use a fusible link that is 4 gauge sizes bigger than the charge wire (e.g., use a 12 gauge fusible link with an 8 gauge wire), or use a high amperage holder.

These directions from Painless are for a 200 amp system with fuse holder, but you can use the same setup and just swap in a 140 amp fuse. https://www.painlessperformance.com/Manuals/30700.pdf

Rick, David & Bruce, thanks for taking time to answer.
Bruce I have the Painless (30700) charge wire kit and talked to CVF about how to run the correct ground from the alternator.
I was "almost" sure I was on the right track about the VOLTMETER. My truck has one as opposed to an AMP meter.
From what I gather, I can run the brown wire of the old 2 wire alternator plug back for the voltmeter.
As info........
My truck is a '83 GMC Sierra Classic 305/700R4 as original.
I have a new 350 engine with the 140 amp 1 wire alternator.
Most of this truck (wiring included) is unmolested.

Thanks again !

 

[Ricko1966]

Plug the brown wire onto a 10 amp fuse. Supply 12v + to the other side of the fuse. Does your gauge read? If so hook the brown wire to a keyed 12v source. You could hook it to the only post on your new alternator, but the gauge will be on forever.