Stator/Rectifier fried

Discussion in 'Electrical' started by silverbackhi, Jul 5, 2011.

  1. silverbackhi

    silverbackhi New Member


    I have a 1982 FXR. If I installed a new battery, that was only partially filled,
    and rode the bike 25 miles......would this cause the stator and rectifier to go bad. One or both may have been bad before the half full battery was installed.
    The bike shop I use are the ones that didn't fill the new battery enough, and they claim this wouldn't cause the problem. I have ridden Harley FX's for 35 years and have burned out rectifiers a number of ways, and have never seen or heard of a stator going bad. I know very little about electrical.


    silverbackhi, Honolulu
  2. Slo-Ryd

    Slo-Ryd Junior Member Contributor

    Last edited: Jul 5, 2011
  3. JBC2565

    JBC2565 Junior Member

    Welcome again. In the self help section under "electrical" is some pictures of burnt out stator's, but you should have a "burnt" smell coming from primary and primary fluid should be very black if you fried your stator.
    Below is a link with good electrical info.
    Harley Davidson Community

    I would also test your voltage regulator to see if that is bad.
    Last edited: Jul 6, 2011
  4. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    If the plates were not fully covered by acid in the battery then the battery would not come up to full voltage
    and the charging system would try to charge the battery as the regulator would sense that the battery was low and send more charge to it this would overheat the battery and warp the plates
    However the magnets in the charging system are permanent so the stator is always producing power any excess power is dumped to earth by the regulator
    excessive need for power by the battery may place extra strain on the stator but i am not sure on this type of charging system
    need help from hoople on this one

  5. Hoople

    Hoople Account Removed

    You did not say if this was a dry filled battery at the time of installing it. It sounds as if it was.
    You really should not take a DRY battery out of a box,, fill it with acid and install it in a vehicle without first charging it.

    The acid will soak into the new dry plates and I would expect to see the level of the acid fall a bit. If after soaking and charging, if the level is now 1/4" below the tops of the plates, installing it into a vehicle under those conditions would NOT damage the VR and stator.
    (On flooded batteries, after adding the acid to a new dry battery, you must charge the battery with a charger before installing it in the vehicle.)

    The big question I now have is how did you make up for the partial acid fill. With a NEW battery, the "soak in" difference must be made up for by adding electrolyte and not with plain distilled water.

    But based on the limited info you supplied (was battery dry filled, prior filled, dry-filled and not charged first, dry filled and charged prior to install etc) I would say the low level of acid did Not damage the stator or regulator. It sounds like what you experienced is the "normal" fall in level (1/4") I would expect to see as the acid soaked into new plates after filling a dry battery out of the box.
  6. glider

    glider Veteran Member


    They should NEVER tell you that. The plates should always be submerged completely or damage to the battery can occur.

    I would use a different indy, they don't seem to have their act together.

    You can top off the battery you have now with distilled water and try from there to see if that's the problem.
  7. silverbackhi

    silverbackhi New Member


    Mahalo everyone for the info

  8. HDDon

    HDDon Experienced Member Contributor Retired Moderators

    Once you have the battery filled make sure that it is fully charged before you install it.
  9. Why was the Battery replaced? the charging system could have been an issue. I work for an independant HD shop in So Cal and I see people buy batteries from us, then return within a week with a new dead battery. its not a knock. it just happens. check for continuity between either of the stator output leads and the engine case. It should have none. should read open line. Any sign of continuity is a sign of a failing stator. A reading of 0.0 ohms means the insulation on the stator windings has been burnt away and the wire is now in bare contact with the engine. If you remove the inspection cover from the outer primary, the smell of burnt plastic will be very strong if this has happened. Always replace the stator and regulator together. when one is failing, it can harm the other.