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my buddy just gave me a set of guages for free (manufacture unknown). they're mechanical guages as far as i know. they include water, oil pressure, and a guage that measures the amps being pulled from or sent to the battery (0-"i forgot how many" on both sides of the needle, which is vertical. yes it does say its for amps) the water and oil are going to be cake, but there was no liturature with the guages. where do i connect the amp guage into my 68 elcam ? or any car?(w/ a/c if that means anything.) ill also ask my budy where he pulled the wires from.

thanks a lot.
 

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Original ammeter was connected with one lead to the junction block behind the battery and the other lead to the horn relay positive terminal. Both leads need a fusible link in them for safety.
I'm not a big fan of hooking up an ammeter like this. Running a couple of extra hot leads inside the car doesn't trill me. Get a meter that measures true voltage.
 

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I'm not a big fan of hooking up an ammeter like this. Running a couple of extra hot leads inside the car doesn't trill me. Get a meter that measures true voltage
Not sure I've ever been trilled, but I have to agree with John. I've seen and repaired too many electrical fire damaged vehicles due to aftermarket underdash ammeters.
 

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Discussion Starter #4
ill just get a volt meter then. to me its not worth the risk. thanks
 

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Getting the Ammeter connected

I have checked out the post in this thread that says the ammeter connects to"the block behind the battery"..... Hmmm, My 77 has no block anywhere close to the battery, only the Right headlight connection plugs. As close as I can figure out by a set of 73 wiring diagrams, one connection is to the hot post (with fusable link) at the solonoid, and the other at the horn relay (big red wire)
Why not just connect to the hot battery post since the juice goes from the hot battery post to the solonoid anyway. It seems the solonoid connection would be much more susceptable to grease road water and debrit. But just because it would be neater and safer doesn't mean that it would be correct.
Hey electrical guru's... help me figure this one out... 8O
 

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“I have checked out the post in this thread that says the ammeter connects to"the block behind the battery"..... Hmmm, My 77 has no block anywhere close to the battery, only the Right headlight connection plugs.”

Right, his was a 68 that had the block. In 72 the wiring routing changed from the way earlier cars were done.


“As close as I can figure out by a set of 73 wiring diagrams, one connection is to the hot post (with fusable link) at the solonoid, and the other at the horn relay (big red wire)
Why not just connect to the hot battery post since the juice goes from the hot battery post to the solonoid anyway. It seems the solonoid connection would be much more susceptable to grease road water and debrit. But just because it would be neater and safer doesn't mean that it would be correct."

Because the meter needs a shunt resistor between the leads. There really isn’t a real resistor. The piece of wire between the two meter leads (solenoid to horn relay) acts like a resistor. The meter is made to work correctly between those two places. (Actually the meter isn’t really an ammeter but I don’t want to go there.)
The car works fine right now with wires attached to the solenoid…right? One more wire down there won’t hurt anything.
 

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I really appreciate your reply. Actually, I have upgraded my pod from the stock idiot lights that came in the '77. I got the nice pod from a 73 SS with the guages, tach etc. I had to rewire the 18 pin connector behind the pod. Everything works great that I have connected so far. I even took out the clock and put in an oil pressure guage that looks like it could have been original (except the clear cover still has the hole for setting the clock)
That said, There was no old circuitry to tap into for the ammeter. I am relying on the 73 diagrams on ammeter connections. Now as you suggested, there may be some other components hidden in the circuit that I don't understand on the diagrams, Hence.... I rely on the expertise of my brother elky lovers. As I understand now, I need to do the solonoid connection, and that should lead me to an accurate, functional ammeter (assuming the meter itself works since it has never been documented by me as functional. just the junkyard guy who swears all works well)
I have fusable links to use, though some say they are more dangerous than nothing or a standard inline fuse. Do you have a recommendation on the fusable links... use them, or use an inline closed fuse (if so, which amp fuse do you suggest?) or just hardwire it in directly?
 

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With an ammeter you measure all of the current flow into the electrical system except the current that goes to the starter motor. A voltmeter is way more useful as it gives you an instant readout on the charging system and battery. I can't think of a good reason to use an ammeter.
 

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Well, didn't want to go here, gets confusing, but the ammeter really isn't an ammeter. It's actually a millivolt meter that measures drop across the shunt wire. Saying that, it isn't measuring all the current going into the car.
The big problem using one of these is if the shunt opens. This can occur if the fusible link, down by the solenoid burns open. This is what it's supposed to do if something big becomes shorted.
Now the ammeter in the car gets full current through it because the shunt wire is open. Cross fingers that the ammeter fusible links blows before the meter fries.
The fusible links should be installed, at the end of ammeter wires furthest from the meter.
 
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