My amp gauge needle is siting 180 degrees from where it should be. I think this happend after I had to jump on the brakes really hard one day. Any chance I can remove the lens and correct the needle?

Thanks, Ken

I had that happen to me,putting a starter in. I lucked up when i sparked it again the needle jumped all the way back around where it should be and been working every sence.

I had that happen to me,putting a starter in. I lucked up when i sparked it again the needle jumped all the way back around where it should be and been working every sence.

Right. The needle will center itself at either the 12 o'clock or 6 o'clock position. If there is a direct short connection it can cause the needle to spin around to 6 o'clock and vice versa. This can intentionally be done without harming the gauge as long as it is a very quick connection (ie: atach the 12V+ lead, then quickly touch the opposite pole of the ammeneter with a ground lead). Hope this helps!
Daniel

If that were the case wouldn't it move as it was charging? Mine just sits there, no movement.

Thanks for the responses

If the gauge is not working at all, then there is another problem. Most likely there is a bad connection within the circuit. An ammeter is a simple little device with a small amount of wire wrapped around a nylon bobbin that contains a circular magnet. Each end of the wire is connected to one of the contact lugs. Current flowing through the wire causes the magnet to deflect one way or the other. The ammeter is part of a complete circuit, so all connections must me made for it to function.

The fact that the needle was able to spin around to 6 0'clock (by simly hitting the brakes hard) probably means that all of the damping fluid has either leaked or evaporated.

If you would like to have the gauge tested and/or repaired, just let me know.
Thanks again!
Daniel

I finally tested my "new" wiring for the ammeter this morning.

I wired a lead directly to the positive battery terminal and one directly to the alternator output. I have fusible links on both wires. Since this is a differential voltmeter, I think that should provide a true positive differential.

When I turned the key to "on" - no movement.

When I started the car, the needle jumped 180 degrees or to the bottom of the gauge.

I reversed the leads and it still operates at the bottom of the gauge. It responds to current changes while the engine is running, like turning on the lights or revving the engine.

I am puzzled why the gauge points downward? :confused:


[EDIT] I just started it again and the needle flipped back around. It actually seems to work properly...at least it moves when a load is introduced. The odd thing is, every time it is turned off, the needle goes 180 out the next time it starts! How weird is that? Maybe some other resistive load needs to be in the line?

Your gauge is showing symptoms of the loss of damping fluid. As mentioned above, the damping oil keeps the needle base stable enough to keep it from making rapid or eratic movements. If the bobbin had the oil inside, the oil would cause enough physical resistance to keep the needle base from spinning when it gets hit with a charge. I can repair this for you at the shop. If you're interested just let me know.
Thanks,
Daniel

Your gauge is showing symptoms of the loss of damping fluid. As mentioned above, the damping oil keeps the needle base stable enough to keep it from making rapid or eratic movements. If the bobbin had the oil inside, the oil would cause enough physical resistance to keep the needle base from spinning when it gets hit with a charge. I can repair this for you at the shop. If you're interested just let me know.
Thanks,
Daniel
First of all, I am interested.

Next, why would it alternate up and down. I mean one time it is at 0 and the next time at 180?

In the simplest of terms.... The ammeter is designed to center itself. None of the the other gauges are designed this way. The damping oil causes slight physical resistance to keep the needle (base) stable. Because there is no resistance from the oil, the electrical input causes the needle to spin around to the next stop point. Just think of the gauge as a tiny "motor". It's a coil of wire wrapped around a bobbin containing a magnet, which spins when an electrical current flows over it. Of course, a motor requires a pos and neg connection, but you get the general idea.

I'm not 100% sure about the wiring connections, but I believe that one of the connections is supposed to go to the horn relay.

You may want to consider replacing the ammeter with a volts gauge. It's a simple install, and provides much better information than an ammeter. I've got restored and calibrated VOLTS gauges listed on ebay HERE (http://www.ebay.com/itm/120902827822?_trksid=p3984.m1586.l2649&item=120902827822&viewitem=&sspagename=STRK:MESELX:IT&vxp=mtr). Mounting plate is included. I'll be glad to help either way.
Thanks! Daniel

http://gaugemarkspicsforweb.homestead.com/VOLTS_CALIBRATED.jpg