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Ammeter issues

Pyrissimus

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How can I bypass the ammeter on my 1970 B Body Charger. The red stud on the ammeter has bad threads. What is the best way around this, other then buying new ammeter.
 
Careful not to conflate the specific information in that “Mad Electrical” article about the later Dodge truck plastic ammeters with the passenger car ammeters of this forum’s era, different animals altogether. Why not repair the ammeter, replace the terminal stud? Plenty of used donor ammeters out there from which to harvest a replacement stud.
 
Bolt both the black and red wire to the good ammeter stud. I'd also run a second wire from the alternator output wire (6 gauge) to the battery. the wires to the ampmeter will power up the dash and nothing else.
Doug
 
Careful not to conflate the specific information in that “Mad Electrical” article about the later Dodge truck plastic ammeters with the passenger car ammeters of this forum’s era, different animals altogether. Why not repair the ammeter, replace the terminal stud? Plenty of used donor ammeters out there from which to harvest a replacement stud.
EXCELLENT INFORMATION AND ADVICE.
BOB RENTON
 
Bolt both the black and red wire to the good ammeter stud. I'd also run a second wire from the alternator output wire (6 gauge) to the battery. the wires to the ampmeter will power up the dash and nothing else.
Doug
Also include an inline fuseable link. Very important.
 
Bolt both the black and red wire to the good ammeter stud. I'd also run a second wire from the alternator output wire (6 gauge) to the battery. the wires to the ampmeter will power up the dash and nothing else.
Doug
If you don't want to replace/fix the ammeter, this works just fine. Add a fusible link/circuit protection to the wire. 8ga wire works well for a stockish alternator. Step up with a potentially higher out put unit.

You can also get a short machine screw, nylock and some elec tape/shrink tube, bolt it together and cover it up. Not using the good stud on ammeter at all.

Get a plug in voltmeter.

Your car, figure out how you want to go.
 
Careful not to conflate the specific information in that “Mad Electrical” article about the later Dodge truck plastic ammeters with the passenger car ammeters of this forum’s era, different animals altogether. Why not repair the ammeter, replace the terminal stud? Plenty of used donor ammeters out there from which to harvest a replacement stud.
I guess carriage bolts are available on the amm stud sizes ? this will allow simply to use a new piece.

Or maybe just rethread the stud ? Where exactly the thread and how deep is gone ? Stud is long enough to use it at any point/ height... just add a nut as a backing nut at a diff stud height. Just thinking out loud
 
I can't find on the ANSI chart the stud and thread specs for a 3/8" AF nut ( nut size for the amm )... smaller size I can find on charts is 7/16" AF which is 1/4"-20 thread for the thread specs.
 
OK, it seems the specs for the stud using the existant 3/8" AF nut should be #10-32 and you can use a 1,5" or 2" lenght carriage bolt to replace the existant amm stud ( which is carriage kind, just not oval head )

10-32 x 2" Carriage Bolts / Full Thread / Steel / Zinc

I guess somewhere could be found on units and not in bulks. Maybe at a local convenience store ?
 
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How can I bypass the ammeter on my 1970 B Body Charger. The red stud on the ammeter has bad threads. What is the best way around this, other then buying new ammeter.
Don't know if you'd be interested, but I have a series on YouTube where I convert the ammeter to a voltmeter and maintain the stock look. If the link doesn't work, search user RetireReady and it's there.

1.jpg
 
Why not install a new replacement ammeter, available from Classic Industries, see below link..
1970 Plymouth Road Runner Parts | Ammeter | Classic Industries

The original Mopar OE electrical system was rated for 50 amps, but this was frequently exceeded when additional accessories like fans, fuel pump, amplifiers reinstalled. To me the biggest weakness are the bulkhead connectors, so if U have added accessories I would recommend U delete the bulkhead connections and go the voltmeter conversion way...

Just my $0.02...
 
Why not install a new replacement ammeter, available from Classic Industries, see below link..
1970 Plymouth Road Runner Parts | Ammeter | Classic Industries

Just my $0.02...
EXCELLENT SUGGESTION.......but....."someone" in the contributing audience will have nothing to say....but....perhaps ask the question: "is it possible for this design to burst into flames or melt down"?.....or....will "the hits just keep on commin' " ??.....
BOB RENTON
 
Jeez, I just see another pristine 54-year old ammeter being mutilated for the installation of a cheap voltmeter. Based on what, “they are known to have problems”? Really? No sign that ammeter has ever had a problem, would have thought it should have spontaneously combusted by now if it was such a problem.

I’ll take a used factory replacement ammeter over any of Chinese repos from Classic. Not sure they cover the non-rallye ammeters any way.

Added loads? Should be connected the alternator side of the ammeter, as are all of the existing factory vehicle loads.

“rated for 50 amps” curiously, where do you see that specified in any factory documentation?
 
Jeez, I just see another pristine 54-year old ammeter being mutilated for the installation of a cheap voltmeter. Based on what, “they are known to have problems”? Really? No sign that ammeter has ever had a problem, would have thought it should have spontaneously combusted by now if it was such a problem.

I’ll take a used factory replacement ammeter over any of Chinese repos from Classic. Not sure they cover the non-rallye ammeters any way.

Added loads? Should be connected the alternator side of the ammeter, as are all of the existing factory vehicle loads.

“rated for 50 amps” curiously, where do you see that specified in any factory documentation?
Note the mopar OER replacement gauges are typically sourced from Taiwan not mainland China, a very big difference in end quality. Don't know exactly what the max the OER ammeter is rated for but scales to +/- 40 amps which matches up well with a traditional mopar electrical system of 1970 origin. If the user has a high output alternator and installed other high current draw accessories than I would recommend he goes with a DC volt meter.


Just my $0.02...
 
No need for that making the things correctly, but also depending on how extreme are the adds on
 
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