KTM 500 exc starter motor fix

Discussion in 'Thumpers' started by Fabnut, Jul 27, 2015.

  1. Fabnut

    Fabnut Been here awhile

    Joined:
    Feb 2, 2012
    Oddometer:
    758
    Location:
    Perth, Western Australia
    Recently starting having problems with the e-start on my '12 KTM500exc over the last couple of weeks with the occasional refusal but lately it just refused to crank at all, with only a clicking from the main start relay. It would kickstart no problems so that narrowed it down to the start circuit of which there is only the relay & the starter itself. My first thought was that the solenoid may have gone in the relay, so as I had a spare for my 690, I threw that in, but still no go.
    Next, I pulled the power lead off the starter itself & tested for voltage there & had 12.8 volts, so I whipped the starter off & pulled it apart to find all the magnets, bar one, had come adrift, lucky they were all stuck to the armature in order, as they are north south pole alternate, so I numbered em all with a bit of tape, cleaned up all the old glue on both the back of the magnets & the housing & re glued em back in as they came out with some 5 min epoxy resin & jammed it back together.

    I gave it a test spin by hooking up the live wire, sat in on the footpeg to earth it & hit the starter, one to see if would actually go at all but also to see if it was turning CCW. Bolted it back up & Bobs your uncle, away she went & just saved myself $400 odd bucks in the process.

    Some of the magnets were a bit chipped but as result of coming loose but after glueing em back in it dosnt seem to hamper the performance of the starter at all & it cranks just fine. One thing I did notice tho while having it apart, was that the flimsy rubber orings that go on the end of the armature housing were a bit stretched & didnt sit well in their groove & as a result theyve allowed water into the unit at some point as it was corroded slightly. Might see if I can find a better solution for that, cos as stock, its not that good.

    IMG_4073.JPG IMG_4074.JPG
    #1
  2. hoorang

    hoorang .

    Joined:
    Feb 16, 2015
    Oddometer:
    1,016
    Location:
    Curlewis NSW
    How many hours on your 500 runt boy?
    #2
  3. Fabnut

    Fabnut Been here awhile

    Joined:
    Feb 2, 2012
    Oddometer:
    758
    Location:
    Perth, Western Australia
    only 65
    #3
  4. rufus

    rufus We're burning daylight...

    Joined:
    Sep 26, 2004
    Oddometer:
    5,560
    Location:
    Coweta Oklahoma

    Looking at the corrosion inside and outside that starter makes me wonder ,............How many of those hours were spent underwater?
    #4
  5. hoorang

    hoorang .

    Joined:
    Feb 16, 2015
    Oddometer:
    1,016
    Location:
    Curlewis NSW
    Thats dissapointing, the sealing has caused some corrosion but it appears parts of the magnet were left behind so adhesive looks to have done part of its job. Might have been a friday arvo special.

    Thanks for sharing I'll check my starter maybe next time the valves are due.
    #5