Ammeter needle movements

[joltesvig]

Should the ammeter needle move slightly negative when I turn the ignition switch on indicating the ignition switch is making contact?
When cranking the engine should the ammeter needle make a large move toward discharge?
If I am charging the battery with battery charger, should the ammeter needle show a large move toward right side?
I don’t know if my ammeter is not working or if the ignition switch is not making contact?
Is there an way to check without any disassembly?

[joltesvig]

PS: In any event, my 31 Coupe won’t start but is getting fuel to the carb.

[alexiskai]

Originally Posted by joltesvig

Should the ammeter needle move slightly negative when I turn the ignition switch on indicating the ignition switch is making contact?

It should move slightly negative most of the time when you turn the key. This indicates that the points are closed. This is why they say not to leave the key on without the engine running for more than about 30 seconds or you risk burning the points from the current going through them. The only time you wouldn't see that is if the engine has stopped in a position where the points are open.

[Y-Blockhead]

To add to what alexiskai said the starter circuit does not go thru the ammeter so you will not see a big - swing when turning over the engine.

And with the battery charger, the charger should be connected directly to the battery so again no swing to the + side.

[alexiskai]

This page has a great breakdown of ignition troubleshooting. Start here.
https://www.grantmaclaren.com/terrystips/

[PalAl]

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alexiskai, thanks for sharing that link, very good reading with lots of information. Some new to me and some a good review. What a great site the "BARN' is!

[Patrick L.]

The ammeter may or may not 'wiggle' while cranking depending on how the terminal box is wired, there was a change during production [ forget what year].

The ammeter should not register when charger is attached.

Tell us what the problem is.....

When you say it won't start, we don't know what that means.
Does the engine turn over [ does the starter work] ?
Have you checked for spark ? Remove plug and place it 1/4" from a good ground, crank the engine over and look for a spark.
Do you have voltage to the points when the moveable arm is open ? And no voltage when arm is closed ?