I'm having some issues when my car is running, it drains the battery. When it is running I get a reading of -60 amps on my ammeter. after I shut it off, it won't start unless I charge the batt. I am not an electrical person so you will have to bare with me. My system is wired like this. 10 ga wire from BATT post on the Alt to the ammeter, then a 10 ga wire from the + side of the ammeter to the hot battery cable connceted to the starter. The plug in on the alt is wired like this: the farthest away lug is jumped back to the BATT post on the alt, and the other to a switched ignition source. I bought the alt from Moon and I ordered a 3 wire alt. With the wire from the plastic plug hooked up to the ignition source I get continuity between the BATT post and ground, and I think that I should not get that. With it disconnected the continuity goes away. Could I have this wired wrong. Could it be a 1 wire shipped by mistake? Or could I be grounding out somewhere else? Any ideas?
what are the voltage readings from each connection on the alternator, relative to ground, when it is not running (key on), and when it is running?
I don't have a real accurate measurement yet, but with the key off I get 12V, on a simple ac/dc meter from the batt post on the alt to ground.
Check it when it's running, see if you get more or less voltage...that will tell you for sure if it's charging or not. Also you might want to ( at least temporarily) run the #10 wire from the alternator output, straight to the battery connection at the starter. That will eliminate the ammeter as a possible problem.
I'll check it out, what should the wire that is supposed to go to an idiot light be hooked to? What would happen if it was removed, does it exite, or start the charging process?
The wire that hooks to your ingnition should have the idiot light tied to it. Basically its there so the alternator sees a load and knows how many amps to kick out, with no bulb means no load....means no charge.
What if I disconnect it? Or should I or could I tie it into onther circut that draws amps, like a fan switch or something?
the regulator in the alternator does not use the idiot light wire to see how much load is on it! it uses the other wire next to it to see how much voltage is at the battery, to see how much it should be charging. Just connect it thru a resistor or idiot light to a switched power source, and dont' worry about it. btw, an idiot light is a better thing to have than an ammeter....in my view, at least. these alternators are pretty much trouble free, until the brushes wear out, and then the idiot light will come on.
With it hookedup right and no accessories on you might see the needle slightly off the center mark. If you turn the lights on it should move alittle more to the charging side if its working right.
no, if it's working right you will only see it charge if the battery needs charging...the needle should not move if you increase the load, as the ammeter is supposed to be connected between the battery and the rest of the electrical system (minus the starter itself). The alternator should increase output enough to cover the additional load of the headlights, without you seeing it on the ammeter.
The extra wire should go thru a 2-4watt bulb. And when you turn on the ignition it should light up. and go out when the engine starts. if you measure the voltage over the battery it should be around 13,7 volt when the engine is above idle.and the altenator is charging. if you have 60 amps drain you have a major problem with the alternator, and or the electrical system maybe you have connected the amp gauge wrong? Do you have a good ground strap between the engine and frame, and frame and battery.
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