Voltage drop

Discussion in 'Electrical' started by Bonzhog, Jul 25, 2016.

  1. Bonzhog

    Bonzhog Member

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    I have a '97 Wide Glide with a 124" ss motor that has starting issues.
    The red wire at the ignition switch gets battery voltage (12.8v)
    When I turn the switch on the red/black wire to the starter relay reads a full volt less(11.8)
    and the green wire at the solenoid is reading around 8-9v when I press the start button.
    Any ideas?
     
  2. tourbox

    tourbox Senior Member

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    With key on you have voltage drop due to headlight/taillight being on. The 12.8 at battery, is that with key on or off. If with key off check with it on. What type starter problems are you having?
    Also would help for more responses to your problem in the right section of the forum. Not everyone reads the new members intro.
    Welcome from So. Texas.
    tourbox
     
  3. Bonzhog

    Bonzhog Member

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    Key on 12.8+ at the battery.
    11.8 red/black at the relay.
    If I put a tender on it battery v goes up as does red/black but still a full bolt difference.
    Do I have to repost the whole thread to the proper section
     
  4. tourbox

    tourbox Senior Member

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    Looking at the top of this page it appears you are in the right section, Electrical.
    What V dc is at the solenoid wire with button pushed, and then again with wire disconnected and button pushed? This starting problem you are having, is it new or old. Did it start after the S&S upgrade? More info would help.
    Remember you have a ACR(electrical) in each head. One could not be activating.
    tourbox
     
  5. Bonzhog

    Bonzhog Member

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    Problem is old and related to changing handlebars. That being said, I replaced the right hand control switches which alleviated some issues.
    Voltage at solenoid wire connected was 8ish
    Disconnected was 10ish
    Today have battery on tender with 13+v.
    At the ignition switch I get the same reading at the red(hot) wire. When I turn switch on I get about a volt less at the red/black wire that goes to starter relay. Thinkin I should replace ignition switch.

    BTW
    Compression releases are working
     
    Last edited by a moderator: Jul 27, 2016
  6. dbmg

    dbmg Experienced Member

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    Have you load tested battery?
     
  7. Bonzhog

    Bonzhog Member

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    Nope but fresh out of the box
     
  8. Jack Klarich

    Jack Klarich Expert Member

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    With key off what is voltage @ battery lug on starter? Now with key on cranking what is it?
    The voltage with key off should be very close to battery voltage
     
  9. Jeff Klarich

    Jeff Klarich Well-Known Member Contributor

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    I'd still load test it, new does not mean it's good. I've seen new batteries right off the shelf that were bad.
     
  10. Bonzhog

    Bonzhog Member

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    Voltage at battery lug on starter is same as battery voltage.