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Sears Fan
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Discussion Starter #1
On my Colt 2712, there is a convienent "dummy light" that lights up if the chargin system is not charging. However, I think I fried my ammeter testing it with a small battery pack (I know, it was a VERY stupid idea...) Without the ammeter, is there an easy way to verify that the generator and voltage regulator is working on my SS12?

Also, is there an easy way to add a dummy light? Maybe use the two leads from where the ammeter hooks up to instead run a light?

I would look on my colt for reference, but it is over an hour away from me :crybaby:

:thanku:
 

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You can replace your fried one with a cheap OVH meter,just remember never touch the grd.lead to nothing but neg.side(grd.) of what your testing-eng.,spark plug,etc.
 

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Just check the battery voltage. Not running it will read 12-13 volts. With it running at full throttle it will be higher, around 14 volts. That indicates that it is charging.

Yes, you can directly replace the ammeter with a lamp. It basically separates the battery from the alternator and shows current flow. If you lose the alternator enough current will flow to light the lamp.
 

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If your ammeter is burnt open, it cannot charge. The charge current passes through it to the battery.

If you have a DC voltmeter that will measure 12VDC with .1 volt resolution, you can monitor the battery voltage. With the engine off, you should have about 12V. With it running at full speed, you should have about 14V.

A panel-mounted voltmeter would be a suitable replacement for an ammeter. Should be able to pick one up at an auto parts store.
 

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ok, so what kind of bulb would I use to replace the ammeter? Just a small incandescent 12v?
A small 12 volt bulb sounds good. Experiment a little and see if it lights with the alternator disconnected. The worst that can happen is that the filament will act like a fuse and disconnect the battery from the rest of the system.
 

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This diagram and schematic shows an optional indicator light for these tractors in addition to the ammeter:

http://sears.pammar.net/h.jpg

The part number comes back as 7198H - No Longer Available, with no further description.

The wiring diagram shows a different hookup for it than just replacing the ammeter, it is wired across the A and S terminals of the starter switch...
 

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Sears Fan
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Discussion Starter #8
Not sure if the ammeter is toast for sure, but i did at one point hook it up to a booster pack, and it tried to hyperextend, now when i turn the lights on, it sticks at 10 and is hard to reset to 0. I know the lights probably draw more than that...
 

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Not sure if the ammeter is toast for sure, but i did at one point hook it up to a booster pack, and it tried to hyperextend, now when i turn the lights on, it sticks at 10 and is hard to reset to 0. I know the lights probably draw more than that...
Yeah, that's pretty bad for it. It's a low impedance meter so when you hooked it across the battery pack it was pretty much a dead short to the battery pack, the same as if you'd used a piece of wire to jumper the battery.

It's only meant to be wired in series, between the battery and other devices, to show much current is flowing in the circuit. Hooking it directly across a battery lets the smoke out.
 
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