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If my alternator coil is out of ohmage, I could add some resistors to it to correct it right? I have seen junk coils with resistors on them, and wondered what they were for, I guess other tinkers have tried this... Any doubts in your minds? anybody tried this and had it fail?
 

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What, exactly, do you mean by 'out of ohmage'?

There are a number of reasons to connect a resistor to a coil, either in parallel or series, but I can't think of one that would apply to a stator coil.
 

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For starters, VERY few VOM / DMM's can accurately measure anything below 5 ohms. Especially so below 2 ohms. Even the resistance of the test leads comes into play...

And if a coil in any sort of electrical motor/generator is showing an out-of-spec resistance, that is PROBABLY because the insulation has burned or chafed away between individual coils, and it needs to be replaced. Essentially you may only have 80 loops of wire instead of 100 if loop #1 is shorted to loop #20.

Adding a resistor to "boost" the resistance of a partially shorted coil ... is only going to REDUCE the maximum possible output of a damaged coil even further.

Suggest you take this to an auto electric shop where they actually REBUILD starters/alternators, have THEM measure it, and/or rewind it for you.

Double check your mfr' specs for the resistance.

Or get a 200/100/50 ohm resistor, put it in series with the coil, apply 12.5 volts, and use ohms law to determine what the ACTUAL resistance is rather than trying to measure a very low resistance. DMM's can measure the VOLTAGE of the battery VERY accurately --- somewhere between 12.5 and 12.8, hopefully, and the amperage fairly accurately.

If your meter doesn't measure amps correctly...check the internal fuse. Someone had the meter set on Amps and performed a volts measurement.

No insult intended Yahmyxs, but...you seem to lack sufficient electrical/electronic background to perform this diagnosis/repair yourself. Suggest you obtain expert advice instead of risking damage to expensive parts.
 

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Adding resistors to "correct" a coil that doesn't check out at the desired resistance will accomplish NOTHING positive and may just make things a whole lot worse! The DC resistance of a coil has little meaning but is often stated just as a "quick check" because the true measure of a coil is impedance but that is difficult to measure.

Don't bugger around with resistors! Replace an out-of-spec coil.
 

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Adding resistors to "correct" a coil that doesn't check out at the desired resistance will accomplish NOTHING positive and may just make things a whole lot worse! The DC resistance of a coil has little meaning but is often stated just as a "quick check" because the true measure of a coil is impedance but that is difficult to measure.

Don't bugger around with resistors! Replace an out-of-spec coil.
DAYYUUMM!!! A Hottie BikerBabe that understands the finer points of electronic theories... I stand in AWE!!

God... I LOVE this forum!!! :biggrin:
 
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