Testing Stator

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Chuey
Posts: 7632
Joined: Mon Aug 02, 2010 11:56 pm

Re: Testing Stator

Post by Chuey »

Well then, I'm going to reinstate my stator alligator, sooner, not later. Then it's up to the instrument cluster to check the pod lights. There's still plenty more to check. Seeing some of these lists as to what can cause these problems is daunting to me. I'm sure that somebody with a better understanding of 'lectricity would have a better idea of where to start. I guess I'm kind of going with the things that get mentioned the most and working my way down to the things I see mentioned less. On mechanical trouble I have a sense of what a noise or symptom would be. This is more mysterious to me.

Is there any reason to be concerned that the rotor tested at 4ohms instead of 3? I have no sense of whether or not that is a significant difference.

Chuey
Garnet
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Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: Testing Stator

Post by Garnet »

Chuey wrote:
Is there any reason to be concerned that the rotor tested at 4ohms instead of 3? I have no sense of whether or not that is a significant difference.

Chuey
There where a whole bunch of rotors with different values over the years, plus now some aftermarket ones. The lower the resistance the higher the current through the rotor, meaning that it will start to charge sooner, get hotter and use up the brushs sooner when at full feild (low RPM).

In other words, it's not a big deal, don't worry, be happy.
Garnet

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Deleted User 287

Re: Testing Stator

Post by Deleted User 287 »

Ken in Oklahoma wrote:
justoneoftheguys wrote: Regarding the stator, more than once have I read accounts of owners chasing an open circuit on one. The problem is is that they static test just fine, but when spinning the centrifugal force opens up the minute break in the winding.
Rob, I believe you meant to say rotor here.


Ken
Thanks Ken.
Chuey
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Joined: Mon Aug 02, 2010 11:56 pm

Re: Testing Stator

Post by Chuey »

This morning after reading Garnet's post saying to not worry, I reattached the stator to the engine and hooked up its wires. Then it was the instrument pod. The "gen" light works when taken out of the pod. That is, the lamp.

Now what? Test Voltage Regulator?

Chuey
Duane Ausherman
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Re: Testing Stator

Post by Duane Ausherman »

You are in the ballpark of resistance, so be happy. There is more.

You can get a false positive from that test. It has happened that a rotor can test OK and not work when hot, or at rpm.

If you found it open, meaning infinite resistance, then you have a bad rotor. Finding 3-4 Ohms is a good sign, but not definitive of a good rotor.

The negative test is 100%, but the positive test can be flawed.
Ask the Indians what happens when you don't control immigration.
Major Softie
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Joined: Tue Aug 03, 2010 1:46 pm

Re: Testing Stator

Post by Major Softie »

Duane Ausherman wrote:You are in the ballpark of resistance, so be happy. There is more.

You can get a false positive from that test. It has happened that a rotor can test OK and not work when hot, or at rpm.

If you found it open, meaning infinite resistance, then you have a bad rotor. Finding 3-4 Ohms is a good sign, but not definitive of a good rotor.

The negative test is 100%, but the positive test can be flawed.
Yeah, negative is 100%. When checking for an existing problem, I'm not sure the positive is even 50%.
MS - out
Garnet
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Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: Testing Stator

Post by Garnet »

Chuey, do I take it that the charge light is not comming on? Or is it just ot charging?

If it's the light, do the rest of the indicator bulbs come on? The nuetral, oil and gen light all get their posative power from the same source in the instrament cluster. The other side of the bulb is connected to one of the brushs on the alt.

The multi pin plug at the back of the cluster is known to give trouble, as is the circut board inside the cluster.

At some point real soon you need to look at a wring diagram and find out the color of the wires.
Garnet

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Chuey
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Joined: Mon Aug 02, 2010 11:56 pm

Re: Testing Stator

Post by Chuey »

At this point I'm going to replace the in dash voltmeter and put the instrument pod back on. I guess if it still doesn't charge, I'll have to learn how to test the voltage regulator.

Chuey
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