Topic: How's this Stator & Coil look?

[bahia]

Took some persuasion and cussing to get it out of the cover.
I think there's a resistance test I can do, but anything else I should know about these?
How's this one look?

[70CB750]

Doesn't look so good.  There must been water under that cover.

[pjlogue]

The formvar (coating on the winding wires) is cooked.  It needs to be rewound. 

-P.

[69cb750]

Stator is bad and rusty from sitting outside engine.

[bryanj]

Ive seen worse work OK you need to do reistance and insulation test

[Bodi]

The stator is pretty rusty but if the wire varnish isn't ruined, it will be OK. Measure resistance between the 3 wires - to each other and to ground. Between wires the resistance should be very close to equal, if any are reading low there is probably a short between windings from the insulation going bad. ANY measurable resistance to ground from any wire means the stator is bad.
Be careful with rust removal, chemicals might attack that varnish insulation. Sand off the rust on the inside diameter though to avoid rubbing on the rotor.
The field coil looks OK, these are hard to kill as the windings are protected better. Again. resistance between its wires should be normal and any resistance to ground is bad.
I don't have the expected coil resistance numbers here. Remember that most meters are not very accurate at low resistance, at least touch the probes together and subtract whatever that resistance reading is.

[bryanj]

Idealy use a megger or similar to test to ground rather than multimeter

[newday777]

Idealy use a megger or similar to test to ground rather than multimeter

I had to look up that one.....megger......

[bryanj]

Uses a higher voltage to test the insulation better

[grcamna2]

Uses a higher voltage to test the insulation better

My father's shop used one of those to test electric motor windings 

[bryanj]

Exactly the thing to use!

[70CB750]

Idealy use a megger or similar to test to ground rather than multimeter

Ha, that brings back memories    My high school was specialized in electrical engineering, our lab hours were very intense, used megger too - just never knew that's what it was called in English. 

[grcamna2]

It'll give you a shock,if you hold both the leads.. 

[PeWe]

Not that big box ready to release 50.000 V ! Adjustable. Not much current, battery driven.
It look like old style volt meter.

I used one at my work decades ago, electrical motors and harnesses to ensure isolation OK.

[bahia]

I think I'm seeing apples and oranges when it comes to measuring the resistance, so I put together a quick video using the multimeter.
Would love some guidance as to if I'm doing this properly and getting the right readings.

[wolf550]

just saw tshrey put his stator and magneto up in the free stuff thread.

[PeWe]

If you think it look like isolation issues, only a Megger will show if OK or not.
It will apply high voltage, very low current during a very short time to verify if it will spark thru damaged isolation.

Check between the phases and each phase to "ground", the cover.
Maybe a workshop working with electrical stuff can test it.

Or if it look OK m, measure the resistances written in shop manual

[bryanj]

Only need megger on yellow(s) to ground to check insulation to ground

[strynboen]

i have vorked at a industri revinding/elektromotor rep shop..faund this old svedish induktor..it can test/give 1000 volt..it have a vhining saund vhen it spools up to give a impuls..it use a 6 volt battery..it only is a megger in the heigest test power..at lower power it test the vindings..for /shorted vires..as it can read presise miliamps differenses in the vindings..
i got it,,as it not have been used for 25 years