Ammeter installation

kwplot34

Heart Attack
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Mar 24, 2008
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Liberty,Mo
How do you hook an AMP gauge in a 71 corvette?? Darrow is a busy man :quote: and does not have time to post his own questions. So can you guy's help Darrow out. Darrow thanks you for your support.
 
How do you hook an AMP gauge in a 71 corvette?? Darrow is a busy man :quote: and does not have time to post his own questions. So can you guy's help Darrow out. Darrow thanks you for your support.

well that is not quite the way it is BUT

I read three electrical drawings and come up with three different ways to do it. What one is right?

Is one side to the generator and the other to ground? The reason for the question is I found a lot of cut wiring and the amp gage is one of them. Also I am changing the oil pressure gage to a sending unit instead of oil pressure due to a problem that I caused. ( need new carpet.)
 
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Sounds like a nightmare to me. I "think" the shunt is in the wiring harness on those. Get an online diagram for 71, and keep tracing/process of elimination.
 
How do you hook an AMP gauge in a 71 corvette?? Darrow is a busy man :quote: and does not have time to post his own questions. So can you guy's help Darrow out. Darrow thanks you for your support.

well that is not quite the way it is BUT

I read three electrical drawings and come up with three different ways to do it. What one is right?

Is one side to the generator and the other to ground? The reason for the question is I found a lot of cut wiring and the amp gage is one of them. Also I am changing the oil pressure gage to a sending unit instead of oil pressure due to a problem that I caused. ( need new carpet.)

No, that would be for a voltmeter.
Out of the firewall junction, you should find a black or orange with a fuse link. That ties into the red charge wire from the alt to the " bat" post on solenoid.

Also out of the firewall junction, should be a black going to the same terminal that feeds the interior power (red) on the horn relay.
 
An ammeter must go in series with the load. It should go between the wire providing power to the fuse block and the fuse block.

To be honest I prefer a volt meter.
 
are the amp meters in or Vettes ture amp meters or are they a volt meter that measures a voltage drop across a shunt and displays it as an amperage?
 
An ammeter must go in series with the load. It should go between the wire providing power to the fuse block and the fuse block.

To be honest I prefer a volt meter.

are the amp meters in or Vettes ture amp meters or are they a volt meter that measures a voltage drop across a shunt and displays it as an amperage?

The factory amp meter I fought years ago, was wired into one of the Alt regulator wires....I forget which now, but it essentially depended on the alt chip to tell it WTF was going on.....that is true for my '72, and wired that way with my entire redo of the harness upon the FI install, was traced out....

so the second post is pretty much correct AFAIK/remember....

and so I switched over to a VM years ago.....

I measure off the IGN/Pink wire....yellow/brown will do....

note that later cars do a Volt meter, and damn rare if ever a Amp meter....

I dunno WTF what was on the minds of the old vette engineers on that amp meter crap....

:crutches:
 
are the amp meters in or Vettes ture amp meters or are they a volt meter that measures a voltage drop across a shunt and displays it as an amperage?

Correct. The shunt is built into the harness.:wink:
 
An ammeter must go in series with the load.

Not always.

Classical electric, it goes across some known wire, which is in fact a resistance to current flow, and so being a voltage drop, and so the meter across said whatever wire measured the VOLTAGE differentail, flowing one way or another....

clever, but to me, useless, because in FACT that meter can be caught measuring hardly any deflection, and yet the battery being drained and not happy with the charge, BTDT, with the stock meter setup to most sharks......which is why I went to a mid 80's chebby pickup VOLTMETER that bolted into the stock '72 shark panel, and gave ME what I wanted....

which is...alt putting out or not, and if so, how much???
 
IF you want brakes on a shark, use Mr GENE'S HYDROBOOST!!!!!


CASE CLOSED@!@@!!!


:shocking:


In the few later sharks I worked on here in Florida, from frame swap to all over electrical problems, I found the worst problems centered around the connecters and especially that white Molex plug on the pass side firewall, found many of them from flat burnt up to turning brown from high resistance, any time you find one of them best to remove it.....especially in a high current application...

I will take a VM over a Amp meter anyday, I HAD the ampmeter in my '72 here, and the alt quit, and hardly noted on the meter, but take a VM to it and one glance told the tale....OUT came that ampmeter.....

another point, when tracing my ampmeter hookup, wonder WTF was with it hardly ever moving, I found it was feeding the regulator on one end....the always live terminal....and that's the way the wiring schematic from GM showed in the service manual.....but this was fought some years ago, don't take my last sentence up there as gospel.....

:shocking:
 
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I used a assembly manual with 71 wiring digrams and taped them togeather so I could follow them. and the wires are a black to battery hot and the black with white stripe to the alternater clip.

Does a volt meter show discharge
 
I used a assembly manual with 71 wiring digrams and taped them togeather so I could follow them. and the wires are a black to battery hot and the black with white stripe to the alternater clip.

Does a volt meter show discharge

Sure does, instantly....14.8 volts when first start engine, dumping alt current into battery, 13.3 or damn close when running for a while, maybe ten minits or so.....if it's ever less than 12.8 you are getting into heavy draw, bunch of cooling fans or HVAC running, headlights on, radio blaring....anything less than 12.8 you are draining the battery....

now with that ampmeter in there, look at the resolution, +- 40 amps in about 1/2" of deflection, center is zero, you can be draining the battery and that ampmeter hardly shows deflection, do it long enough, and you fail to start....lets say you running without AC, and it's daylight, alt is dead, that damn ampmeter will read damn nearly dead on the zero mark, and at a glance no one can tell WTF the thing says....a VM reads 8-16 volts in a 90* sweep, you can tell at a glance, without a microscope....

:club:
 
I used a assembly manual with 71 wiring digrams and taped them togeather so I could follow them. and the wires are a black to battery hot and the black with white stripe to the alternater clip.

Does a volt meter show discharge

Sure does, instantly....14.8 volts when first start engine, dumping alt current into battery, 13.3 or damn close when running for a while, maybe ten minits or so.....if it's ever less than 12.8 you are getting into heavy draw, bunch of cooling fans or HVAC running, headlights on, radio blaring....anything less than 12.8 you are draining the battery....

now with that ampmeter in there, look at the resolution, +- 40 amps in about 1/2" of deflection, center is zero, you can be draining the battery and that ampmeter hardly shows deflection, do it long enough, and you fail to start....lets say you running without AC, and it's daylight, alt is dead, that damn ampmeter will read damn nearly dead on the zero mark, and at a glance no one can tell WTF the thing says....a VM reads 8-16 volts in a 90* sweep, you can tell at a glance, without a microscope....

:club:

Even without hydroboost? You sure about that? I thought hydroboost cured Herpes also.
 
I used a assembly manual with 71 wiring digrams and taped them togeather so I could follow them. and the wires are a black to battery hot and the black with white stripe to the alternater clip.

Does a volt meter show discharge

Sure does, instantly....14.8 volts when first start engine, dumping alt current into battery, 13.3 or damn close when running for a while, maybe ten minits or so.....if it's ever less than 12.8 you are getting into heavy draw, bunch of cooling fans or HVAC running, headlights on, radio blaring....anything less than 12.8 you are draining the battery....

now with that ampmeter in there, look at the resolution, +- 40 amps in about 1/2" of deflection, center is zero, you can be draining the battery and that ampmeter hardly shows deflection, do it long enough, and you fail to start....lets say you running without AC, and it's daylight, alt is dead, that damn ampmeter will read damn nearly dead on the zero mark, and at a glance no one can tell WTF the thing says....a VM reads 8-16 volts in a 90* sweep, you can tell at a glance, without a microscope....

:club:

Even without hydroboost? You sure about that? I thought hydroboost cured Herpes also.

Cures inherent soft brake pedal, that's all......
 
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