Testing The Charging System

[Hoople]

I was at a run last weekend and a couple of friends had '02 Roadkings and they let me test that voltage "back feed" on their bikes because I wasn't real confident in that test either. There wasn't any voltage coming back from the battery. We also did a diode test on theirs and mine (I took it with me) mine was toast.
I have another regulator coming, and I've had a chrome cover on mine and I think this time I'm going to leave it off, it doesn't look like it lets enough air across it to help with cooling.....that might not be the reason I keep blowing regs but it sure can't hurt to try.
Thanks again for all the help.

There were some threads and posts a while back regarding this back-feed test. Some 3 phase regulators had voltage flow some did not. The service manual does reference it for 1 model year, and then a year later there was no reference to it. I therefore still won't call it a 100% valid like I mentioned earlier.

I really would rather use the approach of testing the stator in stand alone mode. If it passes, there just isn't much left to the puzzle. I still believe testing the stator under load as an A/C generator is 1st on the list. Especially if it is 3 phase. You can have 2 of 3 producing which will result in run down batteries and you won't know why because the voltage will in most cases show high enough but current production will be lower than required.

If you have another good sample, as in your case with a friends bike, then yes, both electronic signatures should match and yours did not. So your probably solved your problem. The thing is you still don't know how your stator stacks up and your going to plug it into a brand new regulator. Hummm.

 

[diggerdaveaz]

The thing is you still don't know how your stator stacks up and your going to plug it into a brand new regulator. Hummm.

I checked resistance across the stator pins using the 200ohm setting and it read 0.01 this time. The stator output was around 18vac and increased as the RPM's increased, no stink in the primary fluid either.

A friend of a friend came over and did a diode test on both regulators and both failed, along with the back flow voltage. He said that the testing was all but over unless I wanted to stick my tongue on the leads and check for voltage.....I'll skip that one.

 

[diggerdaveaz]

Ok just an update and some info I haven't seen posted. I'll have to retract my statement about the "back flow for voltage test". Hoople was correct big time, it's extremely unreliable.

I actually don't put too much confidence in that "back feeding" test. Why I can't really tell you, but I just don't. I myself would test the stator as a stand alone AC generator. Then if the regulator output does not meet spec and I know the battery is OK, then the regulator is probably bad.

Also, the smelling the oil part isn't 100% reliable either, mine had zero odor.

Don't waste your time trying to get the compensator nut off with a breaker, it's much easier to get an ELECTRIC impact wrench and *poof* it came off easy and clean.

2002 Roadking...once the compensator nut is off, tape the threads (I used electrical tape) shoot little WD in there and you can wiggle that stator right out of there without taking out the clutch basket. Re-tape any scuffed or bunched up tape, hit the WD again, and with a little grunting it slipped right on.
Thanks again for all of your help, I should have just done it way back when, but reading those manuals can be scary at times. HD-Talking rocks

 

[Hoople]

it's much easier to get an ELECTRIC impact wrench and *poof* it came off easy and clean.

I am very surprised an electric impact wrench could pull off that size bolt. Glad everything worked out and your rolling again. Great feedback => Everyone learned something out of that repair job.

 

[diggerdaveaz]

The electric impact is a little "softer" than an air model, it just tap tap tap then it released, where an air impact may have spun it off before you knew what happened. The shaft itself isn't big, it's just that dang nut that IS.
It's nice to not carry a huge extension cord and a battery charger around....
Now I was given a Power Commander II and I'm trying to figure out whether it will work on my '02 Road King, heck it was free I'll give it a shot at a new life.

 

[ironhead76]

Thank you for the information, you helped comfirm my suspections that the voltage regulator is bad

 

[doc2nd2]

In my 91 FLHTCU I will be needing to replace the regulator and stator. Would it be advisable/possiable or even necessary to replace the unit with the next higher amperage kit? I believe it is a 32 amp system currently.While it has the full compliment of lights, the am/fm cassette and the CB/intercom, I have no other accys than small led accy brake lights (1''X.5'' @2 each).

 

[Jack Klarich]

In my 91 FLHTCU I will be needing to replace the regulator and stator. Would it be advisable/possiable or even necessary to replace the unit with the next higher amperage kit? I believe it is a 32 amp system currently.While it has the full compliment of lights, the am/fm cassette and the CB/intercom, I have no other accys than small led accy brake lights (1''X.5'' @2 each).

It sure would not hurt and you would be on line for more toys when it is done and the higher out put alternators are built better IMO better magnets:s

 

[Hoople]

Like Jack has suggested, if you can "up it" without installation complications or machine work, go for it. You will not overcharge the battery. There are no real negative side effects from doing something like that. The World of Magnets has come a long way in the last 20 years.

 

[diggerdaveaz]

If you buy from a Harley Dealership they will probably sell you a 45amp system, my '02 Roadking is a 38amp system and when I bought the stator they gave me a 45 amp, explaining that they're becoming standard rather than selling two different kits. The regulator will handle both no problem. The only thing suggested to me was to install a 50amp breaker rather than a 40amp (the one by the battery that the regulator runs thru). They're about 10 bucks at any auto parts place.