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For reliability, I'm rewiring almost everything with a Ron Francis kit. They strongly recommend to not wire the ammeter. I'm going to remove it and replace with a new voltmeter.

Question: On the existing gauges, a heat sink on the back of the ammeter connects to the gas gauge:

https://www.dropbox.com/s/qf2ywmv9sxvw4 ... e.pdf?dl=0

That heat sink is for the ammeter, right, so I can remove it?

That is not a heatsink. It is a buss-bar. It passes power to the gauges and I assume there are other blades to connect other gauges.

so as long as I can get 12 V power to each gauge, I don't need the buss bar?

I believe that is correct. It's been a while since I replaced my amp with a volt. I did fuse all my gauges through the fuse block too since I added a couple more to my truck. I used the link below to start on my conversion the 1st time then later put in more relays for high amp circuits. http://www.madelectrical.com/electrical ... uges.shtml
Also our trucks do run 12 volts to the gauges unlike later Mopars that run 5v for the gauges. Here is a link to the wiring diagrams that may be helpful if you don't have them. http://www.sweptline.com/tech/electric.html

gauges do not run on 12 volt. You will burn them up.

powerwagon54 wrote:gauges do not run on 12 volt. You will burn them up.

I thought the early trucks draw voltage right off the accessory power. On my 65 there is no regulator like on my Fury... I'm so sorry if my memory has misled you "hmaynord", Powerwagon54 has tons more experience with these than I do.
Just looking back at my notes from my amp bypass modification...The fuel gauge has the limiter built into it so power hits the fuel gauge first then hits the other gauges. It that right "Powerwagon54"?

40YearOldFury wrote:

powerwagon54 wrote:gauges do not run on 12 volt. You will burn them up.

The fuel gauge has the limiter built into it so power hits the fuel gauge first then hits the other gauges. It that right "Powerwagon54"?

yes, Bud, please confirm, but that must be the answer.
the ammeter and oil pressure light obviously run on 12 V.
the only other gauge that gets < 12V is H2O temp, and I'm leaving that powered as it is: from the gas gauge.
thanks for the links 40YearOldFury.

Here is another thread that shows and explains the detail of the back of the cluster. viewtopic.php?f=21&t=40668&p=290106&hil ... am#p290106
On mine the 12 v comes in and feeds the fuel gauge on the "S" the terminal at the top of the fuel gauge feeds your other 5v gauges...In my case just the temp gauge with a jumper. The remaining terminal on the fuel gauge is the 12v buss-bar that I used to feed my other after market gauges and my volt meter.

Yes power goes to the shunt bar which attaches to the fuel gauge. There is a voltage limiter in the fuel gauge that drops the voltage to 5v.The center post on the fuel gauge feeds the temp gauge only if your truck is 61-68. The center post will feed the temp and oil gauges on a 69-71. But if you touch those gauges with 12v even for a nano second, they are toast.

thanks for the explanations

I did this:

viewtopic.php?f=21&t=35481&p=258557&hil ... ge#p258557

wally, I can't see the photos in your post, but I think I get it.
I think the main difference is that I'm thinking about leaving the gauge in the case.
here is my gauge:
https://www.dropbox.com/s/azmjlxzba4hdc ... e.jpg?dl=0

if everything lines up correctly, here is the part of the gauge that will be seen thru the glass, just the numbers, lines and the word "volts":
https://www.dropbox.com/s/wzjavwta280to ... n.jpg?dl=0

I plan on cutting a hole in the back just large enough to fit the white part thru, but smaller than the black part. Here is a top view:
https://www.dropbox.com/s/opqk9geu9tpxt ... w.jpg?dl=0

probably will need to shorten the black part or lengthen the brass studs.

Lining up the cut of the hole in the back with what can be seen thru the glass will be difficult. If I miss on my first cut and have to enlarge the hole, maybe glue washers on the back to give the black part something to catch on.

why they say don't use an ammeter makes no sense. they are weenies. if you not running 10 high watt spot lights, AC, power windows and a snow plow the amp gauge if fine. only time they are an issue is when you install a high amp alternator and tons of accessories. I love amp gauges way better than volt meters. I know instantly if my charging system is working. if I ever ran a big load and high out put alt. I would just put in a higher capacity amp gauge. there are outfits that will rebuild stock amp gauge to suit high output alternators.

Kaegi wrote:why they say don't use an ammeter makes no sense. they are weenies. if you not running 10 high watt spot lights, AC, power windows and a snow plow the amp gauge if fine. only time they are an issue is when you install a high amp alternator and tons of accessories. I love amp gauges way better than volt meters. I know instantly if my charging system is working. if I ever ran a big load and high out put alt. I would just put in a higher capacity amp gauge. there are outfits that will rebuild stock amp gauge to suit high output alternators.

I love ammeters myself. I do recommend if you retain the stock one keeping it in tip-top shape, or upgrading.

Ammeters let you know the condition of the charging system. Voltmeters let you know the condition of the battery.

Bucky

an ammeter gives you less useful information with more potential problems.

an ammeter was necessary with a generator, mainly to warn of a stuck cut-out relay at shutdown. That kind of potential catastrophe does not apply to an alternator. Now, we just want to know the status of the charging system. On that score, a voltmeter tells you more useful information than an ammeter.
http://www.hotrod.com/articles/hot-rode ... -system-2/

with our particular trucks, the ammeter also has a longer charging circuit, sending all of those amps through less-than-ideal connections. See this article in 40YearOldFury’s Oct 1st post:
http://www.madelectrical.com/electrical ... uges.shtml

I want reliability. So, as part of my rewiring job, I’m changing to a voltmeter. In the process, I get the added benefit of a better monitor of my charging system.

hmaynord wrote:an ammeter gives you less useful information with more potential problems.

an ammeter was necessary with a generator, mainly to warn of a stuck cut-out relay at shutdown. That kind of potential catastrophe does not apply to an alternator. Now, we just want to know the status of the charging system. On that score, a voltmeter tells you more useful information than an ammeter.
http://www.hotrod.com/articles/hot-rode ... -system-2/

with our particular trucks, the ammeter also has a longer charging circuit, sending all of those amps through less-than-ideal connections. See this article in 40YearOldFury’s Oct 1st post:
http://www.madelectrical.com/electrical ... uges.shtml

I want reliability. So, as part of my rewiring job, I’m changing to a voltmeter. In the process, I get the added benefit of a better monitor of my charging system.

sorry but none of that makes any sense. a volt meters give less info. too slow to react if charging system not working. if charging system not working with an ammeter its instantly obvious. with volt meter you wont know until the battery voltage starts dropping.

Kaegi wrote:

hmaynord wrote:an ammeter gives you less useful information with more potential problems.

an ammeter was necessary with a generator, mainly to warn of a stuck cut-out relay at shutdown. That kind of potential catastrophe does not apply to an alternator. Now, we just want to know the status of the charging system. On that score, a voltmeter tells you more useful information than an ammeter.
http://www.hotrod.com/articles/hot-rode ... -system-2/

with our particular trucks, the ammeter also has a longer charging circuit, sending all of those amps through less-than-ideal connections. See this article in 40YearOldFury’s Oct 1st post:
http://www.madelectrical.com/electrical ... uges.shtml

I want reliability. So, as part of my rewiring job, I’m changing to a voltmeter. In the process, I get the added benefit of a better monitor of my charging system.

sorry but none of that makes any sense. a volt meters give less info. too slow to react if charging system not working. if charging system not working with an ammeter its instantly obvious. with volt meter you wont know until the battery voltage starts dropping.

U got that right Steve! Those articles are written by someone with less than basic understanding of electricity, electronics and the actual facts of our trucks electrical system design. Both articles are filled with erroneous and irrelevant information!
Voltmeters are absolutely WORTHLESS in determining whether the system is charging or not. Anyone who states that ammeters are "bad", "useless", "defective", "dangerous" etc, proves by that statement that they don't know what they're talking about!

Wont a voltmeter read 14 something if the system is charging and then 12 something if it is not charging?
jim

Jim100 wrote:Wont a voltmeter read 14 something if the system is charging and then 12 something if it is not charging?
jim

It will read the voltage (pressure) of the system. Theoretically yes, charging system will show higher voltage (about 14) than when not charging (about 12, totally up to the battery).

Bucky