1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

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Hello, I have a 1981 Mercury 50HP Thunderbolt 4 cylinder. I tested the volts and ohm's lastnight with a multimeter. When I tested the blue and blue/white wires from the stator the range in the book was 180-400 volts while cranking. The reading on the multimeter was 260 volts and then after a second it dropped to a range of between 60-80 volts while cranking.
Is this normal or does this mean stator should be replaced.
 

Laddies

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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

You need a DVA so your meter can read the systems voltage
 
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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

I already purchased a new stator this morning just to be sure cause I ordered a new switchbox as well but am curious if the readings I was getting indicate that for a fact the stator is bad or do these fluctuations in voltage while cranking occur normally?
 

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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

The readings are a little high at 260 but the 60 to 80 is to low the spec is 180+. What did the red and red/white read?
 
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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

The red and white reading was 42 volts and the OEM range I had looked up was 25-100 volts
 

Laddies

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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

Yeh it's OK I was wondering about the voltage being a little high at crank speed and whats causing it. must be a bad capacitor or diode in the box
 
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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

Actually I had the wires disconnected from the switchbox when I was testing, does that make a difference. I was thinking the wires were supposed to be disconnected so that if the box is bad there would be no interference?
 

Laddies

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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

That explains the higher voltage, we always test them hooked up and if we have low voltage on one side we disconnect the box to see if it comes up. Here's a test from CDI.
scan0003.jpg
 
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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

Thanks for the input, that's the same chart I used. I was still wondering why I was getting the voltage reading at 260 volts off the blue and blue/white wires imediately at start of cranking and then it would drop to between 60-80 volts, it did this during numerous tests. Is this the sign of a bad stator, or is it somewhat normal for a spike and then drop?
 

Laddies

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Re: 1981 Mercury 50HP Thunderbolt 4 cylinder stator specs, is mine bad?

The is no regulator in the stator so I think that there must be a winding that is burned open and it breaks down as the voltage increases
 
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