Ammeter

[mejum]

I am trying to get my ammeter on my dash to work on my '57. It's the stock dash and ammeter, EZ wiring harness, 12v system.

I've got one 12v lead coming from the starter solenoid (12v constant) and I've got the other line coming from the fuse block that registers 12v when the key is turned on (alternator power).

When I turn the key to the 'on' position or start the truck, the ammeter gauge doesn't move from the D position (it's pegged below the D). I've tried switching the wires and it doesn't move either.

I've tested the ammeter with the multimeter and I am getting continuity so I believe the gauge/ammeter is good.

In theory, this is how the ammeter worked with the factory wiring. I've done some searching and I'm getting mixed results--some suggesting the ammeter works with the leads provided, others suggesting it won't work because of the higher voltage system.

What am I missing or overlooking?

[_Ogre]

the ammeter gauge doesn't move from the D position (it's pegged below the D).

the ammeter should be centered at 0 with key off or battery disconnected

the original ammeter is 30 amps, most of us are running 60 to 100 amp alternators
while the ammeter may work for a while, why risk possible overload or fire in your project?
it can be rewired, but it also requires all power to the panel rerouted thru the ammeter

an ammeter has limited use in a vehicle and has been replaced by the volt meter
i converted my ammeter to a volt meter and did a write up in my thread starting on post 36 and a separate thread

this is a mopar diagram but similar to any ammeter wiring

[tmoble]

What Ogre said. convert that thing to a voltmeter. using that series ammeter with a modern alternator is a fire waiting to happen. It's just not meant to carry that much power. See Ogre's build thread as mentioned. There's a vendor who converts them if you don't want to get into it.

[vintovka]

I thought about it and took a hard look at my original ammeter. Ogre is correct. I would consider converting original ammeters to voltmeters.