Ammeter disassembly

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70Duster340

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Can the ammeter be disassembled? I was thinking of using the body and the screen to install a voltmeter in its place. The mounts are in the correct place, and it would be a better fit than what I have already done.

Thanks!
 
I disassemble a lot of things, They just never fit back together again. Maybe I should use a smaller Hammer ?
 
What I’d like to do it replace the factory ammeter with an aftermarket unit and a shunt and run that.

I'd start by going through the factory service manuals and look for models (guess: 72 Fury) that started using shunt type ammeters. The shunts in those cars were part of the wiring harness, and in some GM, some Mopar, and "most Fords" the design made the ammeter quite "numb". That is, say you turn on your headlights, you had to REALLY look at the damn thing to see "if it moved." This can be changed by changing the shunt---the harness--but what that means is more wire length and more voltage drop

If you do this, at least do so in such a way as to to eliminate the bulkhead connector problem.
 
Here's pictures of what I have to work with:

20210417_142430.jpg


20210417_142440.jpg


20210417_142445.jpg
 
Did you read the thread I posted? There is a tremendous amount of info in there
 
I really like the look of the voltmeter as it is installed in the gauge pod. However, I am having issues with the needle sticking on the gauge face, due to the tight clearance between the needle and the face, caused by adding the backing plate to fill the void in the gauge pod. The gauge is also not accurate, for some reason.
 
Did you read the thread I posted? There is a tremendous amount of info in there
I read the entire post. I guess I could grind off the rivets and remove the ammeter faceplate. Right now I am having some issues with the gauge needle rubbing the faceplate, and getting hung up as a result. Also, it's not properly calibrated. If I can get the needle clear of the faceplate and get it calibrated, I'll be a happy camper!
 

I just skimmed through that article, and what they fail to tell you in it after enlarging the holes in the gage housing is to enlarge them both enough or at the very least enlarge just the plus side stud hole enough to isolate the plus stud coming out of the volt gage so the plus side stud doesnt become a ground short to the gage housing and melt all your wiring.

I did this mod on my 67 barracuda used a sunpro volt gage. The volt gage comes with plastic grommets for the mounting bracket that comes with the gage. What I did was use one of the plastic grommets on the plus side hole of the gage housing I enlarged. I used the plastic grommet along with plastic washers to isolate this side coming through the housing.

The volt gage negative post I grounded directly to the cluster housing using steel washers, and the lock washer and nut that came with the gage since the cluster housing is grounded into the dash frame anyways. This takes care of running an extra negative wire.

The positive wire, I ran a short length of wire to the ignition switched 12V feed going into the IVR (instrument voltage regulator) on the circuit board. On the rallye dash it's a stud going into the fuel gage. On a non rallye dash you can probably solder it right to the 12v feed on the plug in IVR on the back of the circuit board.

Pic shows a red positive and black negative wire. I eliminated the negative wire since the gage housing is the ground, and the negative stud is grounded to it. I only left the red wire. Smaller wires in pic are for a solid state IVR I made to bypass the broken internal one thats inside the rallye dash gas gage. Pic is of back of rallye dash cluster.

Screenshot_20210417-162642_Gallery.jpg


downloadfile-2 (1).jpg
 
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Easy enough to calibrate. With gage out of the cluster, Hook it to a 12v source, use a good volt meter to verify what the exact voltage is, and adjust the potentiometer on the back of the circuit board with a small jeweler's screwdriver to fine tune the needle where you want it to sit at 12V. I clipped the stock needle on the volt gage, and glued the ammeter needle in its place with a daub of super glue. I will be running a denso alternator and so I added a small 12V red led for a discharge light.

Hope this helps
Matt

Screenshot_2016-08-04-17-51-51.jpg


downloadfile-3.jpg
 
Actually in my opinion you should set the cal point at 14V in my Dart, standard cluster, I set 14V right at the old center mark. That is where it should "normally run"
 
I'd start by going through the factory service manuals and look for models (guess: 72 Fury) that started using shunt type ammeters. The shunts in those cars were part of the wiring harness, and in some GM, some Mopar, and "most Fords" the design made the ammeter quite "numb". That is, say you turn on your headlights, you had to REALLY look at the damn thing to see "if it moved." This can be changed by changing the shunt---the harness--but what that means is more wire length and more voltage drop

If you do this, at least do so in such a way as to to eliminate the bulkhead connector problem.


What about this ammeter with the shunt they recommend?

https://www.westach.com/product-page/2c6-3
 
Well, I managed to locate what is the adjustment for the needle. It's a tiny sort of cam lobe behind the needle and only accessible from the bottom. It's a very intricate part, and it has to be done with extreme care due to the location of the copper winding. I managed to trim enough of the backing to allow the gauge face to stop contacting the gauge needle. All in all, it was a painstaking process, but it looks good and is functional.
 
I just skimmed through that article, and what they fail to tell you in it after enlarging the holes in the gage housing is to enlarge them both enough or at the very least enlarge just the plus side stud hole enough to isolate the plus stud coming out of the volt gage so the plus side stud doesnt become a ground short to the gage housing and melt all your wiring.

I did this mod on my 67 barracuda used a sunpro volt gage. The volt gage comes with plastic grommets for the mounting bracket that comes with the gage. What I did was use one of the plastic grommets on the plus side hole of the gage housing I enlarged. I used the plastic grommet along with plastic washers to isolate this side coming through the housing.

The volt gage negative post I grounded directly to the cluster housing using steel washers, and the lock washer and nut that came with the gage since the cluster housing is grounded into the dash frame anyways. This takes care of running an extra negative wire.

The positive wire, I ran a short length of wire to the ignition switched 12V feed going into the IVR (instrument voltage regulator) on the circuit board. On the rallye dash it's a stud going into the fuel gage. On a non rallye dash you can probably solder it right to the 12v feed on the plug in IVR on the back of the circuit board.

Pic shows a red positive and black negative wire. I eliminated the negative wire since the gage housing is the ground, and the negative stud is grounded to it. I only left the red wire. Smaller wires in pic are for a solid state IVR I made to bypass the broken internal one thats inside the rallye dash gas gage. Pic is of back of rallye dash cluster.

View attachment 1715724814

View attachment 1715724815
Looks like I am destined to disassemble the dash yet again to add a grommet to the positive stud. Thanks for the info!
 
Well, I managed to locate what is the adjustment for the needle. It's a tiny sort of cam lobe behind the needle and only accessible from the bottom. It's a very intricate part, and it has to be done with extreme care due to the location of the copper winding. I managed to trim enough of the backing to allow the gauge face to stop contacting the gauge needle. All in all, it was a painstaking process, but it looks good and is functional.
You may be diddling the wrong "adjustment." Mechanical adjustments to the needle are usually for zero adjustments, IE far left, no voltage applied. The original "project" (and the thread I referenced the adjustment is ELECTRICAL. Voltmeters are actually milliameter/ microammeters with what is called a "multiplier resistor" in series to act as a voltmeter. The multiplier in the Sun???? meters used in the original thread has a potentiometer which adjusts the meter reading with voltage applied, so that you can set it where you want on the original ammeter scale.
 
Well, it was never zeroed, so I guess it worked anyway. The needle was left of the "8", so when voltage was applied, it always showed less than 12 volts. The battery being used tests at 12.15 volts, so using this tiny cam lobe I adjusted it so when voltage is applied it reads at 12 volts. That's the only adjustment I could locate.
 
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