Ammeter Wired Correctly?

[Junior]

Trying to figure out if I have the ammeter wired correctly. The ammeter has no markings as to + or -. Dad and I believe the alternator is charging correctly but the ammeter always reads a little below 0 no matter which way we wire it. The ammeter is new as is the wiring harness. This is a 6 volt system w/o cowl lights. Any advise would be greatly appreciated as this is the last gremlin in the harness.

[Bruce Adams]

Turn your lights on and see which way it points.
If it shows DISCHARGE, its OK.

[johnbuckley]

...and if it shows no change there'a fault in your wiring or in the ammeter!...

[Patrick L.]

- is left and + is right.. The original meters were 20 amps and the after markets can be 20 or 30,, maybe more but I haven't seen one.. With everything connected just turn on any lites and see what happens,, meter should read discharge to the left..
If that works correctly then you may have a charge system problem or wiring issue.. If the meter doesn't show a discharge when lites are turned on,, then there is a wiring problem.. You can download a wiring diagram..

[Junior]

So Patrick if I am looking at the ammeter from the front - is left and + is right. If that's the case then from the pic I have it wired wrong (yellow/black wire is positive). Can you confirm this by the photo? Wiring diagrams I have are vague and not clear which side the positive goes to. I will try the light test also.

[Mitch//pa]

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basic diagram

[Junior]

Thanks Mitch. Exactly what I needed.

[Patrick L.]

It'll depend on how you have the system wired,, as to whether you're using + or - ground.. I believe you can purchase alternators either way.. I don't use them on old cars..

[Kurt in NJ]

If it goes to + when you turn on the lights with the engine off switch the wires, if it never moves either power isn't going through it or it doesn't work --if you unhook 1 wire and nothing works power is going through it

[1931 flamingo]

There was a post a while back I think about some of the "new" ammeters being backwards.
Paul in CT

[Tom Wesenberg]

As Paul said, some ammeters read backwards, so you'll just have to reverse the two wires on the rear of the meter if you have a backards reading. Follow the schematic Mitch showed, to make sure the correct wires are on each post in the terminal box and you should get an ammeter reading.

[Junior]

I wired it to the diagram Mitch provided and it works perfect. Turning on the lights shows a discharge. Thanks to all who commented. Hope this thread helps someone else in the future.