How do you check if the alternator is functioning properly.

Discussion in 'Parallel Universe' started by EnderTheX, May 8, 2011.

  1. dpike

    dpike BeeKeeper Supporter

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  2. Jonno.T

    Jonno.T n00b

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    dpike you are a LEGEND.
    Back out to the garage to Get This Done.
    THANK YOU
  3. JRWooden

    JRWooden Homeless motorcycle vagabond ... and ... loving it

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    you did put locktite on the internal bolts right?

    Lube the shafts of the starter reduction gearing before re-assembly.
    The step was added to the shop manual a few versions back...
    I looked up Kluberpaste on the internet and had something similar ... but forget what it was now...
    upload_2020-1-4_21-14-58.png

    Now on to your "real" question:

    upload_2020-1-4_21-15-57.png
  4. rjmorel

    rjmorel Dual Sporticus

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    Why is there so little oil around the stator?
    Would more oil being sloshed around like a 125 Honda single cool it better?
    Why are the cover bolts tightened in the order in the above pic?
    I 'm used to tightening one then going 180 degrees and tighten one then work your way around the case.
    I put grease on my new gaskets and usually it keeps gasket from sticking to cases and not ripping. On my 09 F650GS twin the case gets so hot that it fries the gasket to the case on the exhaust side.
    So with the pandemic I'm thinking in conspiracy mode and thought I'd conspire about my BMW today with these very serious questions.
    :D
  5. JRWooden

    JRWooden Homeless motorcycle vagabond ... and ... loving it

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    Conspiracy R Us....

    I've thought about that too much myself...:photog

    They did fix it in the re-design :fpalm

    Rotax ... / BMW ... really they should have understood this...

    How about this ... they needed all the oil for the clutch?


    I got nuth'n on the bolt sequence..............:dunno
  6. dpike

    dpike BeeKeeper Supporter

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    Loutre and bmwroadsterca like this.
  7. Vandy321

    Vandy321 Adventurer

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    Posted this in another thread, then saw it was from 2014...this thread seems more current.

    Alright, need a quick QC...I'm guessing stator and not R/R is bad, but I also am only learning how to use a multimeter for the first time after reading this thread.

    Connected at plug, checked where wires go into plug: (pics of what connection I'm referecing below, hope uts the right one)
    12.2v DC at battery terminal (key off)
    12.75v DC idle
    12.92v DC at 4k RPM
    - Open Circuit at pins to ground
    - .5ohm between 1-2, 1-3, 2-3
    - AC volts between pins at 3-4k rpm was 12.7, 12.8, 13.5

    Plug disconnected (checked at point of pins of 3 yellow wires)
    -12.2v DC at better terminal (key off)
    -12.75v DC idle
    -12.92v DC at 4k RPM
    - open circuit at ground on 3 yellow pins
    - .3 ohm between 1-2, 1-3, 2-3 (down from .5ohm Connected)
    -3.7-3.9v A/C at each connection 1-2, 1-3, 2-3 (down from 12.7-13.5v with plug disconnected)

    Stator? Why the voltage at pins only 3v unplugged but when plugged in I get 12.7 or so to the back of the pins?

    Pic attached. Did I test anything incorrectly? Suggestions?

    Also, is a good fix to wrap headers in ceramic wrap? This will be the 2nd stator replacement in 10k miles. Previous owner did the first so I don't know if it was a re-build or new

    20210331_172439.jpg 20210331_172434.jpg
  8. flei

    flei cycletherapist

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    Wrapping pipes might help some. But if the stator needs replacing if it has not already been done you also should replace the rotor to the upgraded vented version. That seems to fix the problem most of the time.
    Vandy321 likes this.
  9. CycleDoc59

    CycleDoc59 Wrench Rider

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    With the engine running, A/C voltage across any pair of the the male pin ends (yellow wire outputs from stator), should be around 15-20vac at idle and could be 60vac or thereabouts at 3k+ rpm. Voltage will not be exact from one pair to another, but should be similar. Sometimes when the stator fails, it takes out the rectifier, sometimes not. As you may know, the el-cheapo rectifier is most of the reason the stator fails; the rest of the reason is insufficient cooling for the stator, aggravated by the exhaust pipe location. Thus the stator may look much like a chocolate doughnut, covered with coked oil. At least new stators are cheap now, $75 or less all over ebay. The "fix" is an aftermarket series-type rectifier, such as Shindengen SH-775 and Compu-Fire 55402.. -And yes, wrapping the pipes helps, but that wrap should be sprayed with high-temp paint, not left "raw" as it absorbs water giving you and the bike a steam bath in rainy conditions....
    Vandy321 likes this.
  10. Vandy321

    Vandy321 Adventurer

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    I'll see what rectifier EME sells, they seem to the the go to here in Denver (dealership recommended them over OEM).

    I'm reading that yesterday stator us bad and yoy also think it's worth replacing the RR at same time...its a used bike, so I can ot confirm the history.
  11. Vandy321

    Vandy321 Adventurer

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    Pulled the stator, pic below, not sure how it's supposed to look, but looks a tad burnt up to me. Gonna wrap the headers and also probably throw a new R/R in there.

    Is there a better plug and play RR I should look at, I don't want to go with the series R/R as I need to get back on the road for work and plug and play wiring is key...I currently have the SH5416G-12 R/R

    Thanks in advance

    16172466759638568457660018013096.jpg
  12. RBMann

    RBMann Been here awhile

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  13. JRWooden

    JRWooden Homeless motorcycle vagabond ... and ... loving it

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  14. cathulu

    cathulu Been here awhile

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    Copper is expensive right now... If you buy a cheap stator you are going to get cheap wire insulation. It will lead to another failed stator imho. Buy a good quality stator and try and confirm from the manufacturer insulation at least to 220C and better 240C. The series r/r should help based on reports.
  15. Vandy321

    Vandy321 Adventurer

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    Anybody have the torque specs for the 3 stator screws?

    I found the ones for the crank case cover.
  16. tofire409

    tofire409 Geared up and ready.

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    Looks like 10Nm - according to the Haynes manual.
    Vandy321 likes this.
  17. Vandy321

    Vandy321 Adventurer

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    Thanks!!
  18. Hanzlo

    Hanzlo n00b

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    Hello guys, (Honda cbr 1000 RR 2005) here. Hopefully some of you might help me, I bought a bike 2 weeks ago and I'm having alot of electric problems.

    I have bought new battery, and replaced 2 regulators, thinking they ware the cause of the problem.

    After googling for a week I have found out that I can measure stator AC Output Voltage.

    I have ~12.1 AC Volts coming out of Stator - 3 wires, (bike is turned on, idle) all 3 yellow wires are giving the same reading (~12v).

    Stator looks fine, no burned parts. No ground, and 0.3 Ohms between them.

    Can stator look good and still be faulty?

    The voltage on the battery goes up until bike/temperature rises up to about 50c, then start dropping, also after reving the bike to about 3-4k revs it rises and then drops significalntly from 13.5V+ to 12.5V or so, and then continiues to drop lower and lower, every time I rev the bike same thing happens, up and then drop.

    Thank You!
  19. ebrabaek

    ebrabaek Long timer

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    Your stator is bad assuming you are testing the stator wires while unplugged.
    Have a look in the other charging thread here.
    It will give you a step by step trouble shooting steps.
  20. Hanzlo

    Hanzlo n00b

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    Yes, i have tested it while unplugged. I have read all 18 pages of this thread :). Noone had exactly the same problem :S.

    I have ordered a new stator, hopefully, that will fix the problem. Can there be anything else causing this malfunction?