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Bobcat 773 C Series (97′) Won’t Shut Off

bnjmnmccrorie ยท 2010-04-28 19:47

I have a Bobcat 773 and I have a weird problem going on that I cannot figure out. Out of the blue a few years back the machine would not shut off, turn the key and control system shuts off but the engine keeps on running. I have checked out the ignition switch and it seams to be working properly, I have checked the wiring harness and traced all the wiring to the fuel shut off selonoid and relay everything looks fine. Then I unhooked the alternator and then everything works like it should, I have to charge the battery manualy but at least the machine shuts off. I dont have any slow electricity draws, the machine can sit for a month and not loose a battery charge. I guess my next step is going to be to test the relay and selenoid to see if Im getting stray voltage from somewhere besides the ignition. Anyone have any thoughts? Thanks.....BEN

Replies3
  1. #1willie592010-04-28 20:00

    Sounds like you need to have your alternator rebuilt. You probably have a bad diode inside the alternator that operates a battery light on the cab console. If the diode goes bad, it will put voltage current on the ignition circuit while alternator is turning (engine running). This would keep the shut down solenoid powered up and make engine continue running after turning key off.

  2. #2bnjmnmccrorie2010-04-28 21:57

    I guess my next step will be to pull out the alternator and have it checked out. Thanks alot for your time and I will let you know what I find out....BEN

  3. #3bnjmnmccrorie2010-05-23 10:41

    Won't shut off update Just posting what I found...I hooked the alternator back up...I had unhooked it a year ago and Ive just been charging the battery on the machine when I'm not using it. With the alternator hooked up now the machine shuts off just fine. What I did notice is that after hooking it up and the machine sitting for a week or so that something is drawing down the battery and I know it has something to do with the alternator. So now I'm just unhooking the neg terminal when the machine sits. I figure I will have the alternator rebuilt the next time I service the machine.