Ampmeter gauge acting up

[Gerry]

OK, my gauge worked fine before the swap but after the swap it works opposite what it should ie. shows discharge when charging and vice a versa. I am sure it has something to do with the MSD ignition system, coil and the starter. I am going to reverse the wires to the gauge and see if that fixes it but I was wondering if anybody has any thoughts on this. Thanks in advance.

Best regards,
Gerry

 

[Geek's 65]

Gerry. What "swap"? You swapped the guage? Reversing the wires won't hurt anything and as long as it shows correctly (i.e you leave the key off and turn on the headlights - it shows a discharge and when you start it it shows a charge) then I would say no harm no foul. When I rewired my car, both the fuel guage and the volts were bassackwards. Reversed the wires and all was well. I called LL who made my harness and they said that it's not unusual in their experience to find rebuilt and reproductions that were done backwards.


Geek

 

[studiog]

OK, my gauge worked fine before the swap but after the swap it works opposite what it should ie. shows discharge when charging and vice a versa. I am sure it has something to do with the MSD ignition system, coil and the starter. I am going to reverse the wires to the gauge and see if that fixes it but I was wondering if anybody has any thoughts on this. Thanks in advance.

Best regards,
Gerry

I may be all wet on this but I am getting ready to hook mine up and I was under the impression that it would work backwards if hookup backwards as DC voltage flows in one direction and wiring backwards would change the direction of the current flow.

 

[Gerry]

I may be all wet on this but I am getting ready to hook mine up and I was under the impression that it would work backwards if hookup backwards as DC voltage flows in one direction and wiring backwards would change the direction of the current flow.

Sorry, I swapped the original 427/M20 for a 540 Shafiroff and a Keisler 5 spd.
Yes, I believe that reversing the wires would correct the situation and the no harm no foul rule applies. But, I want to know why current is now flowing in the opposite direction. What can I say I'm a scientist and I gotta know this or I won't be able to sleep. Thanks for the help.

Best regards,
Gerry

 

[studiog]

Sorry, I swapped the original 427/M20 for a 540 Shafiroff and a Keisler 5 spd.
Yes, I believe that reversing the wires would correct the situation and the no harm no foul rule applies. But, I want to know why current is now flowing in the opposite direction. What can I say I'm a scientist and I gotta know this or I won't be able to sleep. Thanks for the help.

Best regards,
Gerry

Maybe you're rewired in such a way that all your feeds are not routed through the ammeter anymore. Just a thought.

 

[JohnZ]

Maybe you're rewired in such a way that all your feeds are not routed through the ammeter anymore. Just a thought.

Two entirely different animals (circuits) here - C1's have a true "ammeter", where all the power from the battery goes through the ammeter, which then feeds the fuse block and the rest of the car; on C2's, it isn't an "ammeter" at all, and doesn't carry any operating current - one wire goes to the horn relay buss and the other goes to the battery cable stud on the starter, and the "Battery" gauge is simply a sensitive voltmeter, which measures the voltage present at those two points and displays the difference between them as "amps" to indicate whether current is flowing "to" or "from" the battery.

 

[studiog]

Two entirely different animals (circuits) here - C1's have a true "ammeter", where all the power from the battery goes through the ammeter, which then feeds the fuse block and the rest of the car; on C2's, it isn't an "ammeter" at all, and doesn't carry any operating current - one wire goes to the horn relay buss and the other goes to the battery cable stud on the starter, and the "Battery" gauge is simply a sensitive voltmeter, which measures the voltage present at those two points and displays the difference between them as "amps" to indicate whether current is flowing "to" or "from" the battery.

Thanks again John for clearing that up.