How can I test alernator rotor on the bench

[Dr Bobs Patient]

First off, I have searched a lot of the alternator threads here and on the WWW and have not been able to find an answer.

Here's the background: 99 IS; 68,000+ miles; bike quit running on a ride, tested battery and it would not hold a charge - replaced it; 60 miles later bike dies again;  found a small bike repair shop and put a 3 hour charge on battery.  Mechanic there tested the alternator and said it was toast - no output;  disabled as much electronics and lights as I could and made it 80 miles towards home and had to trailer it the last 30 miles;  Pulled the alternator cleaned it up and replaced the brushes as they were worn out; reinstalled it and that didn't solved the problem - still no output; pulled it out again; On the bench, the stator wiring meters out with continuity on all three windings;  that leaves the rotor and the voltage regulator to test;

Should there be continuity or resistance (Ohms) on the rotor contacts rings where the brushes ride?

There is continuity from the rings to the windings so there's not a break where the windings start.

Could the regulator on the stator be bad?

I know that sending it out for rebuild or just replacing it would be preferable but I am broke and will try the cheapest route first.  Any help would be appreciated.  I'm not afraid to try any repair. 

[Robert]

Generally it seems the rotor windings are a problem they were manufactured in China and have been the source of alot of troubles. A rebuilt alternator from M.A.R.S is not that expensive. I doubt you will get out for less than one of these choices with a lot less aggravation.


Here are some links for you, one is a 40 amp and one is a 90 if you look at the old posts you will find that both were in stalled by guys with little or no problem. All options are under 200.00 and of course there is a used alternator from a place like Pinwheels

http://www.rareelectrical.com/p-7423-new-honda-valkyrie-alternator-lr140-718a-lr140-718b-31100mz0005-31100mz0015.aspx

http://www.ebay.com/itm/HIGH-OUTPUT-ALTERNATOR-Honda-Gold-Wing-Aspencade-Interstate-1520cc-GL1500-90-AMP-/261084225465?pt=Motorcycles_Parts_Accessories&fits=Make%3AHonda|Model%3AValkyrie&hash=item3cc9d51fb9&vxp=mtr

http://stores.ebay.com/PinWall-Cycle-Parts-Inc/Honda-/_i.html?_fsub=3437893014&_sid=12458664&_trksid=p4634.c0.m322

http://www.valkyrieforum.com/bbs/index.php?topic=18689.20

[NCGhostrider]

Check your Honda service manual.  It has basic testing for our alternator components...

You can do a rudimentary test by checking for shorts from the slip rings (the area where the brushes touch) to the metal that usually encases the center of the rotor.  The problem is, that it may not show a problem under load.  You have already tested for basic continuity.

We use a tester that actually applies voltage and looks for shorts.  Often it will fail that test and still pass a simple ohm test.  We test the stator windings the same way, and look for a balance  between the wire sets.

All that said, the regulator would be a common failure, and is on most alternators.  Usually, and I think this is this case on the valks/goldwings (I think I looked this up before my trip), the brush holder is combined with the regulator.  They are to be replaced together but not required (fairly inexpensive).  The manual gives brush replacement instructions.   

Stator failure and even rotor failure or more common when bearings fail and metal rubs against metal.  Of course vibration breaks may occur because of faulty manufacturing, as mentioned.

Also fairly common is rectifier failure.  Output will often start out diminished, heat continues to build and will take the remainder of the rectification system. 

I know these are not specific for your failure.  But the principles apply.  I see it most everyday in my little shop.  The guy that works for me is the expert, not me.  If you can find a good alternator shop near you, he can help you out with parts and testing.  Be sure and tell him to look it up under the GL1500 Goldwing series.   A repair should be cheap if the major components are good. 

BTW, most alternator and starter parts are coming from China these days.  I see supposedly American made products with Chinese parts in them.  The same ones that get put back in them for repair.  Sad, but true.   I recently had a high torque starter for a modified GM engine in the shop.  The owner had paid several hundred dollars for it.  It had been rebadged, and was of course Chinese made.   It should have sold for about 1/2 or less than he paid for it.  Not defending the Chinese stuff, but its a reality.

My .02

Craig
NcGhostrider
99 I/S

[gordonv]

Sorry, but sometimes I'm a little thick. You say the alt has no output. Where did you test for power? At the alt, or at the battery?

There is a fuse between the alt and battery.

[Dr Bobs Patient]

Sorry, but sometimes I'm a little thick. You say the alt has no output. Where did you test for power? At the alt, or at the battery?

There is a fuse between the alt and battery.

Both.

[Dr Bobs Patient]

Thanks NCGHOSTRIDER for your information.  I have been reading a lot about alternators....more time than money.  And thank you ROBERT for the links if I need them.

I've found a regulator for $48 online (probably China) and might give that a try.

Thanks again fellow Valkyrie Riders.

[NCGhostrider]

Just curious.. Did you get your alternator fixed?

I checked the price of that regulator/brush assembly.  It should retail for around $40 and some change. 

I have one setting on my desk now from my vendor, I just haven't had time to check it against the OEM to see if it matches.   And I am not in the mindset to pull mine off since it still works.  I will just carry a spare brush/regulator set with me on the road.

I need to get a not working alternator from one of our valks and do a tear down to see what is actually there.   I could then post pics and more information on a rebuild for everyone that is inclined to do the repairs themselves.

Craig
NcGhostrider
99 I/S

[gordonv]

I tore my regulator off my damaged alternator, thinking it would be easier to change that as an assembly while on the road, since it houses the brushes also, but I think it could only be done in a shop.

Still wouldn't hurt to carry it, instead of just brushes, when on the road. But I also doubt you could change brushes yourself either, so it would need to be done at a shop anyways.