L/C Kawi alternator starts discharging 10 imnutes after blades are engaged ???

Discussion in 'Mechanic and Repair' started by MJB, Jul 31, 2008.

  1. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    Exmark Lazer Z 22hp L/C Kawi .... As stated above it starts discharging only when the blades have been engaged for a while and it will drain the battery fairly quickly. If I let it run without the blades engaged it will charge back up.
    I replaced the battery, and the alternator with a rebuilt one regulator is mounted on it. I checked and changed a few safety switches, which don't appear to have anything to do with this problem.

    Any suggestions Is it in the pto switch...clutch.... I'm stumped and this is the one thing I'm terrible at diagnosing electrical problems.

    Just to let you know I put ona rebuilt alternator which was $160. a new one from Exmark was $365 I think. The only thing I was unshure of was the regulator it looked identical but did not have any writing on it volts , amps etc
    Thanks for any help. :dizzy:
     
  2. MowerMedic77

    MowerMedic77 LawnSite Bronze Member
    Posts: 1,164

    Do you have a DVOM or something to give us some voltage readings so we can have a better idea of were the drop is? Have you checked the simple things, good ground, fuses, burnt/corroded/loose, electrical connections?
     
  3. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    I've got a digital multi tester. Will that work?
     
  4. sawman65

    sawman65 LawnSite Senior Member
    Posts: 751

    if i recall corectly the lc kaw's have a external regulator i would replace with what came on it.
     
  5. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    If I could find just the regulator that would be great, but my Exmark dealer told me I had to buy the alternator reg combo for $360 ? If I could just get the regulator I would save a bunch if in fact that is the problem. I'll contact another Exmark dealer to see what they say.
     
  6. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    How many volts, or amps should the alternator be putting out and what is the best way to test it?? Here is a pic of it on the mower. I tested the upper red wire on the left side and the small black wire on the right and got over 14 I don't remember exactly, but it seems that it is working. But the battery shows the voltage dropping when the longer the engine runs even without the deck engaged. Need help finding the problem.

    Exmark Lazer Z AS 024.jpg
     
  7. kawasaki1

    kawasaki1 LawnSite Member
    Posts: 108

    if it's a belt drive alternator, is the belt tight?
     
  8. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    The belt is not slipping. I have as tight as I can get it without going to a shorter belt. But I need to know how many volts coming out of the alternator & regulator should it have when it's running. I've noticed a slight discharge when I put the meter on it. So I may have something else wrong between the alternator and the battery. Just not sure where to look.
     
  9. kawasaki1

    kawasaki1 LawnSite Member
    Posts: 108

    i'm pretty sure that alt. has the regulator built into it.

    find the wire that shows battery voltage with the key on, engine not running. it's probably the big red one.

    if the wire shows voltage start the engine and see if voltage goes up.

    if you have no voltage with the key on, look for a bad wire or blown fuse. alternators need some battery voltage going to them to be able to charge.

    if you have voltage but it doesn't go up when running, take the alt. to autozone or someplace and have them check it.
     
  10. MJB

    MJB LawnSite Silver Member
    from Wa
    Posts: 2,869

    Thanks I'll try it tommorrow, the shiny chrome on the back is the regulator. So you are right about that.
     

Share This Page