Need help with a Kymco starting issue.

Discussion in 'Battle Scooters' started by eakins, Aug 21, 2016.

  1. aguim

    aguim Been here awhile

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    'a voltage between frame and ground' sounds like 'a voltage between ground and ground'. I know
    electrics can get a bit tricky, but this one needs an explanation...
    #21
  2. shovelstrokeed

    shovelstrokeed Long timer

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    How about a simple bad battery. Remove the battery, most auto parts stores have the ability to load test your battery. If it doesn't hold voltage during cranking, it needs replacement.
    #22
  3. Sootgrinder

    Sootgrinder Been here awhile

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    Yep sounds like just a bad battery to me.
    #23
  4. pnw

    pnw Long timer

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    Battery was my suggestion also. My scooter acted almost the same with a bad (lithium) battery. Started every time without an issue using a lithium jump start battery (the Walmart cheap kind), I must have used the jump starter about a dozen or more times on a trip without having to recharge it and even then when I got home it was nearly fully charged, since my scooter doesn't have a kick start I carry one with me all of the time now.

    A bad cell in the scooter battery was the problem. Apparently a battery can reach fully charged voltage but not handle a load. When I got home I put the old lead acid battery (that had worked before) but that didn't work either even after charging it. A new battery solved the problem. There is a chance of two bad batteries in a row.

    It will be interesting what you finally come up with.
    #24
  5. eakins

    eakins Butler Maps

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    Taking it to an auto parts store today.
    It's the 3rd battery to do this however, have starting problems within a week so something else is going on.

    I contacted Kymco and they provided me a contact for one of their techs to help me troubleshoot the root of the problem.
    #25
  6. eakins

    eakins Butler Maps

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    ok here are things i tested in this order.
    battery fully charged overnight.

    cold engine

    key off - .01 amp draw between neg battery & ground. no parasitic drain.
    key on - 5.40 amp draw. normal range?

    key off - 12.8v
    key on - holds steady at 11.9v for well over a minute (no drop)

    engine starts like a champ & runs well.

    13.9v while running

    turn engine off for 1 minute

    key off - 12.5v
    key on - voltage drops quickly to bellow 11 in less than 30 sec

    will not start now.

    -------------------------------------------------------------

    so I get 1 good start, then something happens?

    heading now to parts store to test load ability of battery.
    normally I would say this is a bad battery, but it's the 3rd in a row so something is causing batteries to fail???

    PO added a tender because of starting problems.
    shop I bought from added a new battery (traditional Interstate) when delivered, as the one in there had problems.
    this battery failed after a few day, so I bought the biggest AGM that would fit (175cca).
    this battery is failing after a week.
    #26
  7. eakins

    eakins Butler Maps

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    that was a miss-type.
    #27
  8. eakins

    eakins Butler Maps

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    did another test. voltage drop while starting from 2 points (fresh charged battery)

    -connected direct to battery: 10.6v or so see on tester while starting.
    -connected to possitive & negative on starter: 8.6v or

    It happens so fast but that is approx a 2v difference?
    #28
  9. Beezer

    Beezer Long timer Supporter

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    5 amps sounds pretty normal, even maybe as much as 10.

    sounds like something warms up and becomes a conductor. I'm guessing it is the Regulator Rectifier. after the 1st start, leave it running but unplug the R/R & see if the battery still goes flat. it won't charge, but it shouldn't drop as low as what you have been seeing

    if thats ok, after the 1st start, when the battery voltage is falling, pull off the battery cable and measure the current draw again to see if it increases from cold. (assuming the engine runs off a mag type CDI & can operate with no battery... it may not)

    as for the 2 volt drop on your last test, that may be in the starter relay contacts and cable. test that by putting one lead on the starter + and the other on battery +.... when the starter is engaged that should read zero volts (in theory.... there is always a small drop) it should not read 2 volts. anything over a fraction indicates resistance from bad connections. but that is not the excessive draw killing the battery.
    #29
  10. bwallca

    bwallca Been here awhile

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    #30
  11. Beezer

    Beezer Long timer Supporter

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    and ... 'a voltage between ground and ground'. that connection is made by a cable. you only have voltage drops across conductors because of excess resistance (bad connections, corrosion inside the wire,etc). its the same as what I posted above about the battery, relay path to the starter that is possibly causing the 2v drop. apparently that was a miss-read, but it is possible to get such readings and it is something to check since the circuit completes through the structure.
    #31
  12. eakins

    eakins Butler Maps

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    well the battery is fully charged, but only 90% and did test bad.

    taking the previous battery back to parts store and see how that test.
    found out the previous owner replaced the factory battery too before he traded (got sick of this problem?) it in.

    so in 1000 miles this engine has gone thru 4 batteries. 2 in the last 2 months while I owned it.

    i can't be believe that it was 4 bad batteries in a row.
    something is killing these batteries.

    where next?
    #32
  13. eakins

    eakins Butler Maps

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    even though I have a marginal battery now, engine still starts after it has a full charge then often does not want to start the next time.
    how about a ground fault in the ignition or starter button?
    #33
  14. eakins

    eakins Butler Maps

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    tested battery #3, bad too.

    it's not just they drain or there is resistance to starter, something is killing these batteries & that is the root of the my problem.
    #34
  15. andyman7931

    andyman7931 Adventurer

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    what kind of charger are you using on the battery? could it be the problem?
    #35
  16. eakins

    eakins Butler Maps

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    think I found a/the problem.

    started digging into the alternator charging coil, ignition pulse sensor & reg/rec

    -alternator charging coil (yellow wires from motor) all in spec (.05 ohm & no ground continuity) - good
    -Ignition pulse sensor (from motor) 101.5 ohm (spec 106 ohm) - close enough?
    -reg/rec yellow wires (connects to charging coil yellow) no ohms (spec is .04-.06) - problem!

    so the reg/rec seems bad (no ohms on the yellow wires) but I was still getting 14v charging to the battery? does this seem right? the 14v was steady no matter the rpm from idle to high rpm. thought this was odd as I was expecting it to be lower at idle.
    #36
  17. eakins

    eakins Butler Maps

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    tender jr. works just fine on many other things with a battery. not the issue.
    #37
  18. eakins

    eakins Butler Maps

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  19. eakins

    eakins Butler Maps

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  20. Jay_In_Milpitas

    Jay_In_Milpitas Zero to sixty in February

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    Eakins, some auto parts stores can test starter motors (a tester that also tests auto alternators via belt drive). Perhaps give that a shot?

    Also, I'm wondering if the solenoid might be sticking, allowing the starter to draw currant and the alternator can't keep up.
    #40