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No, but I got a working one sitting in my garage in case yours is bad...

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If you do the voltage test at the battery while the engine is running is should be 14 volts at 1000rpm.
If this doesn't check out, you then have to find out whether it's the stator or rectifier. Check the ac magneto charging coil resistance (right at the coupler) with your testor set to ohms. If this test checks out then its the rectifier, if it fails then it's your stator.
If you want to tackle this yourself, I would suggest you download the service manual here and refer to page 9-25. This would be the easiest to understand.
 

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If you do the voltage test at the battery while the engine is running is should be 14 volts at 1000rpm.
If this doesn't check out, you then have to find out whether it's the stator or rectifier. Check the ac magneto charging coil resistance (right at the coupler) with your testor set to ohms. If this test checks out then its the rectifier, if it fails then it's your stator.
If you want to tackle this yourself, I would suggest you download the service manual here and refer to page 9-25. This would be the easiest to understand.
In addition to step 4 on page 9-25 where it shows the charging coil resistance ohms check:
1-2 and 1-3 you also need to check 2-3 doesn't state that in the service manual but you need to ohms check those leads also.
WARNING do not ground the terminals with the test leads you will need to change your stator for sure if this happens....just an FYI
 

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yes, make sure you have a full battery charge before you start.
 

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Discussion Starter · #9 ·
thanks, have it on a charger now, will wait till tommorow so the battery is fully charged
 

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do i check the resistance with the engine running?
NO... Resistance is measured with the engine off. If you are measuring the AC voltage that the stator is putting out, then the engine needs to be running. An external voltage into a meter in resistance mode (Ohms) has a real good chance of frying the meter. The comment about grounding out one of the stator leads and frying the stator is true only if the engine is running.

That said, the resistance of the coils is very low; essentially a milliohm-meter is needed to measure accurately. Most multimeters do not have a range low enough to measure it and the meter reads a dead short, even with a good stator. This is where measuring the AC voltage output comes in, as you can do this with any multimeter set in AC volts mode. You should see about the same AC voltage between any and all combinations of the output leads (the 3 combinations stated previously). That AC voltage should be around 20 volts AC or more.

Be sure that you are in AC volts mode and in the correct range to make the measurement. You can verify that the meter is working correctly by CAREFULLY sticking the probes into a wall receptacle. You should measure 110 VAC there.
 

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That said, the resistance of the coils is very low; essentially a milliohm-meter is needed to measure accurately. Most multimeters do not have a range low enough to measure it and the meter reads a dead short, even with a good stator. This is where measuring the AC voltage output comes in, as you can do this with any multimeter set in AC volts mode. You should see about the same AC voltage between any and all combinations of the output leads (the 3 combinations stated previously). That AC voltage should be around 20 volts AC or more
Excellent advice!
I was thinking the same thing as I hit the "submit reply " button.
An analog needle style voltage tester would be required to test the ohm resistance because it's so low ,but they don't say that in the service manual.
Most people have a digital testor so testing the AC output would be the better way as described by SteveS.
 

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thanks, have it on a charger now, will wait till tommorow so the battery is fully charged
I appoligize for the misinformation, thanks Steve for the correction.
I have a stock stator that your more than welcome to if yours checks out bad.
 

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And yes , I would check in the AC mode, your already set up for it.
 

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Discussion Starter · #14 ·
thanks for the info, my multimeter doesn't go low enough to measure, but it does make needle move slightly on two pair, but not the third, but if i change the leads around and put neg. on #1 and #2 it reads way different actually puts needle half way to dead short, shouldn't it read the same no matter what lead of the meter i use?
 

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Now that I'm not sure. If you follow the way it's done in the manual you leave the + lead on #1 and only move the - lead to #2 and #3. What is the coil resistance readings you're getting?
 

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breto, do you have a copy of the service manual?
 

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Discussion Starter · #17 · (Edited)
hard to read my multimeter since its a cheapo, had resistance between #1 and #3, and between #2 and #3 but none with #1 and#2. Started motor and tried to read ac voltage and had nothing on any pair, assuming bad stator.
I do have service manual
 

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thanks for the info, my multimeter doesn't go low enough to measure, but it does make needle move slightly on two pair, but not the third, but if i change the leads around and put neg. on #1 and #2 it reads way different actually puts needle half way to dead short, shouldn't it read the same no matter what lead of the meter i use?
I'm not sure that you have meaningful measurements when the needle is barely moving. When 2 sets of coils measure differently than the third, that is usually a sign that one set is somehow bad, but with the unreliability of the measurement you cannot be sure.

I'm not sure what is going on with the different measurement when you reverse the leads. That is usually related to meauring a diode circuit (current flows differently depending on polarity). I can see 2 possibilities: Have you disconnected the rectifier from the stator; there are diodes in that box to rectify the AC to DC and that would perhaps cause what you are seeing. Second; check for corrosion on the pins that you are probing. It's really a stretch, but corrosion can act as a rectifier under the right conditions.

Have you tried the meter in AC voltage mode, with the engine running and the rectifier disconnected? That will give you a much clearer picture of what is going on. If one or more sets of coils are low output, then you know for sure that the stator has a problem.
 

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Discussion Starter · #19 ·
When checking ac voltage I had the rectifier plugged in, no voltage on any pair. Do I need to check voltage with the rectifier unplugged? When I checked resistance the rectifier was plugged in, it shouldn't matter should it?
 

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When checking ac voltage I had the rectifier plugged in, no voltage on any pair. Do I need to check voltage with the rectifier unplugged? When I checked resistance the rectifier was plugged in, it shouldn't matter should it?
I would do either test with the rectifier unplugged, If the rectifier is faulty it could affect the test. For example, an open diode in the rectifier could conceivably cause a different reading when reversing the leads if the diodes are in the circuit being tested for resistance. If the rectifier is internally shorted, it could drag down the voltage output of the stator.
 
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