Replacing Ammeter with Voltmeter?

Posted By: char69ger

Replacing Ammeter with Voltmeter? - 08/22/12 06:06 PM

I have searched the board and found references to a MAD conversion site but the link doesn't work. I also read that it was in the tech archives but nothing there either. Anyone have the instructions for replacing the ammeter with a voltmeter?
Thanks

Posted By: Dodgem

Re: Replacing Ammeter with Voltmeter? - 08/22/12 06:16 PM

This is what I did take one side wire off back of amp meter and but together with other wire this by passes gauge all you need!
One (+) from volt meter can also be hooked on hear for it's 12V source mount and ground and your done! No more non charging and starts!

Posted By: Challenger 1

Re: Replacing Ammeter with Voltmeter? - 08/22/12 06:23 PM

I think it would be neat to have plug in volt meter you could stick in to your cit lighter.

Posted By: Dodgem

Re: Replacing Ammeter with Voltmeter? - 08/22/12 06:24 PM

Or you can do this

now same deal except you run power from alternator to starter relay then into car instead or in through and back out stock

Since I have my battery in the trunk it's alt to battery then through cut off switch to starter relay and in leaving all stock wires in place but wire that would have gone to back bolt on alternator is cut short and taped in case one ever wanted to go back stock.

Posted By: Dodgem

Re: Replacing Ammeter with Voltmeter? - 08/22/12 06:27 PM

Quote:

I think it would be neat to have plug in volt meter you could stick in to your cit lighter.

Like this??

http://www.campingworld.com/shopping/item/12-24-volt-lcd-voltage-meter/19983

even i'm surprised they existed

Posted By: Challenger 1

Re: Replacing Ammeter with Voltmeter? - 08/22/12 06:40 PM

Quote:

Quote:

I think it would be neat to have plug in volt meter you could stick in to your cit lighter.

Like this??

http://www.campingworld.com/shopping/item/12-24-volt-lcd-voltage-meter/19983

even i'm surprised they existed

Yes!!! I'm getting one!!! I just bought a AC unit from them, wished I would have ordered it then, thanks.

Posted By: Chal340

Re: Replacing Ammeter with Voltmeter? - 08/22/12 07:42 PM

Quote:

I have searched the board and found references to a MAD conversion site but the link doesn't work. I also read that it was in the tech archives but nothing there either. Anyone have the instructions for replacing the ammeter with a voltmeter?
Thanks

the link to MAD conversion : Here

Posted By: Dodgem

Re: Replacing Ammeter with Voltmeter? - 08/22/12 08:10 PM

the link to MAD conversion : Here

Dam looks like my picture wonder where I got it??

Posted By: char69ger

Re: Replacing Ammeter with Voltmeter? - 08/22/12 08:12 PM

Thanks for the info guys. As usual this is the place to get my questions answered quickly.
Lee

Posted By: GreenBird

Re: Replacing Ammeter with Voltmeter? - 08/23/12 06:52 PM

If I can just hijack this thread, now that the main question was answered, is that 14 gauge fusible link shown in the MAD diagram heavy enough to carry the current on the charging wire from the alternator to the battery? What would be the equivalent size fuse to use, rather than fusible link? IIRC, when I did my wiring I initially used a 30 amp fuse but it blew right away so apparently was not heavy enough. I now do not have that wire fused but connected directly and it is making me nervous. I have the 60 amp denso alternator in a 69 Road Runner with 500ci engine. Voltmeter is showing normal charging.

Posted By: stumpy

Re: Replacing Ammeter with Voltmeter? - 08/23/12 08:21 PM

There is a reason for a fusible link vs a fuse. The links can take a power draw surge for a while but a fuse can only take it for a split second.

Posted By: ahy

Re: Replacing Ammeter with Voltmeter? - 08/23/12 10:36 PM

Quote:

If I can just hijack this thread, now that the main question was answered, is that 14 gauge fusible link shown in the MAD diagram heavy enough to carry the current on the charging wire from the alternator to the battery? What would be the equivalent size fuse to use, rather than fusible link? IIRC, when I did my wiring I initially used a 30 amp fuse but it blew right away so apparently was not heavy enough. I now do not have that wire fused but connected directly and it is making me nervous. I have the 60 amp denso alternator in a 69 Road Runner with 500ci engine. Voltmeter is showing normal charging.

It depends on ammeter size. On a '70 the charge wire was 12 guage, fusible link 16 guage and the alternator rated around 50 amps. Maybe the 14 guage fusible link + 10 guage charge wire is good for 60-70 amps intermittant.

With a big alternator, I just don't think its a good idea to route charging current into the pass compartment at all. On mine that has a 100A alternator I run 6 guage wire and a 10 guage fusible link right to the fender relay.

The voltmeter is hooked to the power supply for the instrument panel which is ignition switched. If the volt meter is not on a switched circuit it will eventually drain the battery.

Posted By: roadrunninMark

Re: Replacing Ammeter with Voltmeter? - 08/23/12 11:02 PM

has anyone tried to make a voltmeter gauge that looks stock and replaces the ammeter in the dash?

Posted By: Sinitro

Re: Replacing Ammeter with Voltmeter? - 08/23/12 11:10 PM

Quote:

has anyone tried to make a voltmeter gauge that looks stock and replaces the ammeter in the dash?

Straight forward...
Use another basic guage (temp, oil pressure) shunt it with a resistor. Guage is essentially a 5VDC, and change its scale.
Red Line can do the whole thing, pretty qwik.

Contact Shannon @ Red Line Guages..
Redline Gauge Works
23347 Newhall Avenue
Santa Clarita, CA 91321
Phone: 661.259.8891
Fax: 661.259.9177
Email: info@redlinegaugeworks.com

Just my $0.02..

Posted By: mjb765

Re: Replacing Ammeter with Voltmeter? - 08/24/12 03:23 AM

If you bypass the ammeter completely and run wiring direct from alternator to battery, couldn't you use 8 gauge wire with a 12 gauge fusible link??

And what about a 1 wire alternator?

Posted By: ahy

Re: Replacing Ammeter with Voltmeter? - 08/24/12 03:39 AM

Quote:

If you bypass the ammeter completely and run wiring direct from alternator to battery, couldn't you use 8 gauge wire with a 12 gauge fusible link??

And what about a 1 wire alternator?

Yes and yes. 8 guage wire and a 12 guage fusible link would be good up to 100 amps or so. It would also work fine with a single wire alternator... with volt meter to monitor system condition.

Posted By: mjb765

Re: Replacing Ammeter with Voltmeter? - 08/24/12 03:55 AM

So run the one wire direct from the alternator to the battery terminal on the starter relay and protect with fusible link? Bypass the ammeter in the dash and leave everything else as is?

Posted By: MoparMarq

Re: Replacing Ammeter with Voltmeter? - 08/24/12 05:21 AM

Quote:

has anyone tried to make a voltmeter gauge that looks stock and replaces the ammeter in the dash?

Did one on '72 RR using voltmeter out of a Isuzu Trooper. Ehrenberg also did one in same type of dash (71-74 B-body) in an issue of Mopar Action sometime in the last year or so, IIRC. Not sure, but I think it was an Autometer gauge guts.

There've been a few threads on this subject over the last year or so.

BTW, the +12V side of the voltmeter should be on a switched source (ignition, accessory bus, whatever), not hot all the time. Unless of course you want the battery to run down...

Posted By: GreenBird

Re: Replacing Ammeter with Voltmeter? - 08/24/12 05:39 PM

Quote:

So run the one wire direct from the alternator to the battery terminal on the starter relay and protect with fusible link? Bypass the ammeter in the dash and leave everything else as is?

My question basically was the same as this one. I have followed the MAD diagram, bypassing the ammeter, and have a charging wire running directly from the alernator to starter relay. OK to fuse that charging wire with the 14 gauge fusible link as shown in the MAD diagram?

Posted By: mjb765

Re: Replacing Ammeter with Voltmeter? - 08/24/12 06:06 PM

Quote:

Quote:

So run the one wire direct from the alternator to the battery terminal on the starter relay and protect with fusible link? Bypass the ammeter in the dash and leave everything else as is?

My question basically was the same as this one. I have followed the MAD diagram, bypassing the ammeter, and have a charging wire running directly from the alernator to starter relay. OK to fuse that charging wire with the 14 gauge fusible link as shown in the MAD diagram?

As I understand it, you run the fusible link 2 sizes (numerically a difference of 4) smaller than the wire....8 gauge wire uses a 12 gauge fusible link, 10 gauge wire uses a 14 gauge fusible link, etc.

Posted By: GreenBird

Re: Replacing Ammeter with Voltmeter? - 08/24/12 06:16 PM

Thanks.

Posted By: astjp2

Re: Replacing Ammeter with Voltmeter? - 08/10/20 02:26 PM

not 100% accurate, you can get slow blow fuses, the windings in them have a heat sink that will allow the fuse to adsorb more of the over-current for a longer period before it blows but they are not as cheap as a fuseable link. Tim

Posted By: NachoRT74

Re: Replacing Ammeter with Voltmeter? - 08/10/20 04:59 PM

Originally Posted by char69ger

found references to a MAD conversion site but the link doesn't work.

THANKS GOD!!!!

Posted By: earlymopar

Re: Replacing Ammeter with Voltmeter? - 08/10/20 07:19 PM

Ha! Good comment Nacho! I personally used your dual-circuit idea to cut the load on the OEM wiring in my 65' Dodge pickup and it worked perfectly. You know your stuff.

- EM

Posted By: challenger70

Re: Replacing Ammeter with Voltmeter? - 08/10/20 09:39 PM

I did this as close to factory as you can get, works great. Have him go through everything and convert your clock to quartz while your at it.

Originally Posted by Sinitro

Quote

has anyone tried to make a voltmeter gauge that looks stock and replaces the ammeter in the dash?

Posted By: NachoRT74

Re: Replacing Ammeter with Voltmeter? - 08/12/20 07:14 AM

Originally Posted by earlymopar

Ha! Good comment Nacho! I personally used your dual-circuit idea to cut the load on the OEM wiring in my 65' Dodge pickup and it worked perfectly. You know your stuff.

- EM

Cool!

That saves the bulkhead, then a powerful alternator ( opposing to the ppl beliefs) will save the ammeter!

Posted By: NachoRT74

Re: Replacing Ammeter with Voltmeter? - 08/12/20 08:30 AM

Originally Posted by NachoRT74

Originally Posted by char69ger

found references to a MAD conversion site but the link doesn't work.

THANKS GOD!!!!

Unfortunately is still working! DAMN!

Posted By: mopowers

Re: Replacing Ammeter with Voltmeter? - 08/13/20 03:00 AM

Originally Posted by earlymopar

Ha! Good comment Nacho! I personally used your dual-circuit idea to cut the load on the OEM wiring in my 65' Dodge pickup and it worked perfectly. You know your stuff.

- EM

What is the dual-circuit idea?

Posted By: NachoRT74

Re: Replacing Ammeter with Voltmeter? - 08/13/20 09:19 AM

Originally Posted by mopowers

Originally Posted by earlymopar

Ha! Good comment Nacho! I personally used your dual-circuit idea to cut the load on the OEM wiring in my 65' Dodge pickup and it worked perfectly. You know your stuff.

- EM

What is the dual-circuit idea?

Is about save the weak link paths at bulkhead... but accomplished with a better higher output alt able to assure a good iddle output capacity.

http://www.dodgecharger.com/forum/index.php/topic,33574.0/all.html

The parallel circuit is an upgrade if the stock system is still good and in working order or needing just a mantenience job. But once is completely damaged ( and you don't care for restore it ) can be simply replaced by a full single circuit job making the full bypass of the original paths for the charging circuit, BUT NOT LIKE MADELECTRICAL says. Stock ammeter can still work safe making things right.