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New issue new thread to my 41 110….just rewired it back to 6 volt system with the help of many on this forum….started it up for first time and it fired right up, however, my ammeter needle is buried to the right and does not move at all when running or activating the lights…it’s a new voltage regulator and rebuilt generator all correct for car…I polarized the generator..the ammeter needle has been in this position since it was converted to 12 volts and they used an aftermarket battery gauge mounted under dash,,,so I’m wondering if my ammeter is not working or there is something wrong with the generator or regulator..I’m getting about 5.9 volts at the generator at idle and same at BATT and ARM terminals at regulator..my battery is at around 6 volts at idle and goes up about 6.6 when reving engine…any thoughts would be appreciated tks.
Or any ways to test regulator and generator …the literature I have found is pretty complicated for me to understand as a newbie

Is the ammeter even wired up?

Honestly I suspect the needle is just stuck. It should point at the middle when the car is off, and a 12V conversion should not damage an ammeter unless they did something stupid like passed a dead short through it sometime.

It may be stuck…took it for a 2 hour drive and battery was fully charged when I returned…so I’m assuming rebuilt generator and regulator are working correctly..

Yeah the only way that needle can be pegged that far up normally is if you have a healthy but very discharged battery, are driving at a good speed, and are using no accessories.

This is from a 1940, but that delicate needle bends easily and can get stuck at either of those two tab stops OR be pressed too close to the face of the gauge. Sometimes tapping it from the outside will release it, but you may have tried that. Otherwise, remove it and see if it is simply stuck and returns to the center position when you release it. You'd have to remove it to replace it anyway.

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Ok thanks…I just did a continuity test with and I’m getting continuity between the two terminals…I don’t know if that’s bad or good….I ran wires from both terminals and tested on battery ..there is a little spark at battery but no movement at needle..I can also see a piece of what looks like thin cardboard running from terminal to terminal it’s one piece that is bolted down by both terminal base nuts…I don’t know what that is either…any thoughts? Before I yank it…ok I just got a light on the needle and I believe you are right ..it looks like the needle went over the max stop and not stuck on the other side..I guess I’ll have to remove it…but thanks for the info..I never would have looked that close at the tabs…

The cardboard is simply an insulator and by your description it seems that the gauge is physically stuck so will need to be removed for service.

An ammeter is basically a loop of wire between the terminals and the size of the wire depends on how much current the ammeter is designed to handle since except for the starter motor almost all other current a car uses flows thru the ammeter. The loop can be actual wire or just a stamped piece of flat brass or copper bent in such a fashion as to form a loop. Using an ohmmeter to test between terminals should read a direct short but there should be no reading between either terminal and the case. The purpose of the cardboard is to keep the bulky wire terminals from touching the case if the wires got pulled or terminals are accidentally bent.

A simple explanation on operation is that as current passes thru the loop of wire it turns it into a weak electromagnet with north and south poles. That magnetism attracts a piece of iron that is also slightly magnetized and attached to the needle. When no current is flowing the needle is kept in the middle, sometimes by gravity of the piece of iron attached to the needle and in other designs by a small hairspring. In a simple car ammeter, if the car is charging the more the current is flowing from the generator thru the ammeter to the battery the stronger the magnetic field in the loop of wire will be and the more the needle moves. If the current flows in the opposite direction such as when a discharge is occurring from the battery the same thing happens only the magnetic poles in the loop of wire are reversed so the needle moves the opposite direction.

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I politely suggest you review what an ammeter even is and how it's wired into the car's electrical system, if the answer is not obvious.

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I wouldn't do this as you can damage your ammeter or the battery, though if you just tapped it briefly it's probably fine.

To me it just sounds like the needle is stuck. I would remove it an do a careful mechanical inspection.

Ok ..I. Going to pull it today..thanks!