6v Stator coils resistance ranges needed please

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johnny650
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I have spent all morning searching the net trying to find some data on the resistance ranges for the original 6v points stator coils without success. There are loads of references to 12v electronic stator coils and pickups but not the old 6v points .? :?

Does anyone have the resistances or can direct me to a link somewhere please .....I'm stomping around the place like a bear with a sore head today. :lol:
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garry inglis
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johnny650
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brilliant !... thank you garry. I have looked everywhere for the 6v tests.
Guess nobody uses 6v points stators anymore
Muppet
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6v or 12v them numbers is not rite
C’est la vie
johnny650
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mmm think you're right about that Muppet .
I've just measured the resistance on four x 6v points stators and I don't get anything like that.

the LT coil 1.2 ohms
small pink coil 0.4 ohms
large pink coil 0.3 ohms
small purple coil 2.5v
large brown coil 1.4 ohms
firekdp
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Muppet wrote: Thu Nov 15, 2018 9:42 pm 6v or 12v them numbers is not rite
They are probably correct for that discussion on a vintage car forum, possibly HT coil primary resistance. :D
firekdp
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The reason you don't see the figures for standard stator resistances is the readings are very small, most around 1ohm or less. So finding a problem within a few shorted coils would be undetectable with a standard ohmmeter and the contact pressure of the meter probes themselves can vary the readings given.
These old coils are pretty reliable though and most problems are down to poor joints/connections. Damage to the coil itself will normally be viewable as physical damage to the enamel coating or heat damage.
Although saying this, your readings on some are a little out from what I'd expect.
johnny650
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mmm that makes sense... thanks for posting
I have been struggling to make sense of the readings I have been getting on the half dozen stators I have checked.
Readings have varied all over the place for the same coil on each stator.

From what you've said it sounds like coils with any reading of 0.3-1.0 ohms is likely to be useable
A reading of 0 ohms is clearly a coil with an open circuit and useless
Slightly high ohms say 1.6-1.8 ohms probably indicates a poor contact with meter probes or a dirty or poor soldered joint with a bit of resistance but still quite useable.

The more you go into components the more you see potential problems that are easily missed.
Today whilst checking a stator I happened to notice that the top edge of all the coil laminates had a bright wear mark . It looks like the flywheel I have been using is shorting out the magnets via the coil laminates !... that can't be good for starting and running reliability lol
firekdp
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johnny650 wrote: Fri Nov 16, 2018 8:09 pm From what you've said it sounds like coils with any reading of 0.3-1.0 ohms is likely to be useable
A reading of 0 ohms is clearly a coil with an open circuit and useless
Slightly high ohms say 1.6-1.8 ohms probably indicates a poor contact with meter probes or a dirty or poor soldered joint with a bit of resistance but still quite useable.
Not really, what I meant was that if there was a short within the coil itself, it would not be discernable on a ohmmeter reading.
For example, a main lighting coil, being a relatively low number of turns of thicker wire, would have a reading of about 0.3 ohms, so a few shorted turns isn't going to be noticeable at all.Any difference in this reading and I'd be looking at the wiring to the coil for the problem, not the coil itself.
The pilot light coil has the most windings/thinnest gauge wire (approx 280 T of 0.5mm) this I would expect to measure about 2.5ohms.
Ignition and brake light coils are wound for very similar wattage outputs so are both around the 1 ohm mark.
All of these windings are quite substantial compared to the very fine diameter wire used on electronic systems, so any damage to them is mainly mechanical and visible by eye.
johnny650
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thanks for the detailed explanation , I hadn't thought about approaching this from the point of view of required voltage output of the stator coils. I have searched the net for hours and not found anything definitive anywhere.

I really should fit the electronic system I have and have done with it but I'm a tenacious sob and don't give up easily.
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