Hughs PMA Regulator Overheating?

I had to go out and check. Not really a detent but it does fell solid as youturn the key. Not hard to turn just solid. Like in old cars when you closed the door it felt and sounded solid. Not like new cars that sound like a beer can crunching.
Leo
 
Right on, I'll probably stop by Tractor Supply Co tomorrow and check one of the others because mine has nothing.
 
Little update. Put a different switch in it, it ran fine for a few days then started acting up. Checked my stator and it had zero resistance, although it was not grounding out. I ordered a new one from Hugh, got it in last night, and it is doing the EXACT same thing as before. All the grounds are good, and I've been through the wiring several times and cannot find anything wrong. Whats next? Push it into the river?
 
Well I found out the impedance function of my multimeter crapped out, so I just picked up an Actron CP7677. I tested the new stator which is fine, and I shot the regulator and got a reading of 408 on diode test. When I shot yellow to ground I got nothing with the black electrode on ground and red on any of the yellows, but got 408 with the red electrode on ground and black on all three yellows.
When testing to the positive out of the reg/rec I got 408 from red electrodes on yellow wires to black on reg/rec out and nothing with the electrodes reversed.
Is this the correct way to test this? If so are these readings any good?
 
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Well I found a good charging system trouble shooting tree. I made it to checking the AC voltage off the stator and that's where it went south. I only got maybe 8 volts at idle and it dropped to 3 or 4 or less at high rpm. I double checked and the meter was set to AC volts at the 200 range. I even checked it on a wall outlet to make sure it was reading correct. The stator ohms checked good, hot and cold with no grounds. The woodruff key is in the crank, I gave it a check wiggle to ensure it wouldn't move before I tightened the nut. Is it possible the stator is not lining up correctly in the flywheel? I'm using an aftermarket adjustable banshee bracket if it matters. I know the flywheel is seating on the crank by the surfaces of them when I removed it.
 

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Take out the woodruff key, see if that changes anything. I've had a few folks make a poor fitting key, and it hold the flywheel a bit "off" of the crank - see if you have any indication that the stator is touching the flywheel

hugh
 
Take out the woodruff key, see if that changes anything. I've had a few folks make a poor fitting key, and it hold the flywheel a bit "off" of the crank - see if you have any indication that the stator is touching the flywheel

hugh

Just tried it. I measured the flywheel distance from the stator bracket with and without the woodruff key and it was about the same. Maybe 1/64" difference if anything. I tried the stator output check again with the reg hooked up and got the same readings. Tried it with the stator disconnected and the coil running off my spare battery and seemed to get a good reading. It was around 45-50 volts on all three circuits at a higher rpm. Not sure exactly how fast since I don't have a tach and wasn't revving the hell out of it, but it seemed to be a good reading. I'm thinking it's a bed reg/rec.
 
I just ran the rest of the tests as per my fault code tree and got the same 450 readings as before. I even called customer support for my meter to make sure there isn't a missing decimal in there I didn't know about and he said there is not, for a good diode there should be a reading of about 0.7 volts.
 
A diode is a one way valve for electricity. To test a diode you use the ohms scale. Test it one way then reverse the leads. If good the reading one way should be at least 10 times the other way.
On a three pase rectifier their are two sets of three diodes. Three of these diodes hook between the positive wire and the three wires the same color, often yellow or white. Three are hooked between the negative wire and the three colored wires.
Sometimes the positive wire can be red or green. Sometimes the negative wire can be colors other than black. Depends on whhat bike they are for.
To test a rectifier you put the red lead on the positive wire, touch the black lead to the three colored wires, write down the ohms. Now reverse the leads. Write down the ohms.
Now do the same tests using the negative wire.
From the positive to the three should read high or low ohms, reversing the leads should read the opposite. If high the first time, low the second.
From the negative to the three will test the opposite. If the positive was high the first test thenm the negative will be low on the first test.
Your repair manual tells how to test a recifier. The PMA should test the same way.
Leo
 
I used the diode test function which reads in volts. I can try it again using ohms.
 
Tested using ohms in the 200k range. Got readings around 86 one way and 137 the other...
 
That sounds a bit close on the readings. I think we should get Punkskalar in on this.
I think he could give us a bit of his knowledge.
Leo
 
I can't think of anything else it could be. The wiring is all good and the stator is putting out sufficient volts so I'm thinking the regulator is working erratically. Just out of curiosity, I'm assuming it's OK to have the reg/rec mounted to bare steel right?
 
In the Clymer manual page 39-40 is the test for the stock rectifier. On the 70-73 it calls for 75-150 ohms one way, infinity the other. 74 up is 9-10 ohms one way, infinity the other.
In my Clymer book for my Honda CM400, it uses a PMA charging system, the recifier specs are one way 5-40 ohms, the other at least 2000 ohms.
Is your reg/rec a new or used unit?
The mounting should be bare metal to bare metal. Or very near it. This helps pull the heat out of the reg/rec into the frame. Paint or powder coat insulates the body of the reg/rec from the frame. A light coat of heat sink grease to help the heat transfer and prevent corrosion will help.
Leo
 
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Good deal, it's mounted on the steel strap under the seat for the fake oil bag. It's on bare steel but only one bolt holds it on. It does have very good ventilation though. I had the solid state reg for the old charging system mounted the exact same place and it never skipped a beat.
 
At this point we can ask if some one with a PMA can test there reg/rec ohms and see how they compare to yours.
If I think of it I'll check my Honda's reg/rec tommorow after work to see how it ohms out.
It has a charging problem but it's the stator. On that stator I get ohms on the three yellow wires of .9 ohms, .9 ohms .4 ohms. Checking the ac output of the three yellow wires is 11 volts, 10.5 volts and 4.8 volts. with the reg/rec plugged in. Without the reg/rec plugged in I get 28 volts, 28 volts and 8 volts. So this indicates a bad stator. I didn't check the reg/rec.
Leo
 
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