I had an unusual problem yesterday. My machine was running fine but when I went to,turn the machine off the engine stopped running but the starter could be heard cranking the engine with the key off. I then tried the key in all positions with no change, the starter kept cranking the engine until the battery died. I'm assuming this is a faulty switch but could anyone confirm this or suggest other possibilities? Thanks
Sounds like a Starter solenoid issue. Didn't figure there was too many folks on here from AK!
Yep, 90% chance it's the contacts stuck on the solenoid. I went to one once where a screw had fallen between the plates in the solenoid. A lot of times if the solenoid sticks you can pull a battery cable off and when you put it back on, it'll work fine. Sometimes tapping on the solenoid while the cable is off will work. Anytime you see this, you should pull or cut a cable if you can, it's less damaging than letting it run until the battery is dead.
You are probably right but why didnt the machine start back up when I turned the key to the on position as it. Was cranking out of control? Thanks
Probably Because the starter drive gear can't engage the stationary flywheel ring gear while it is turning at very high speed.
Thanks but it certainly sounded as though the engine was turning over.
You got me, then. Perhaps an anti-restart function in the electronics? I don't know Bobcat much, but I've seen this problem many times on things from a p'up to a 988, it was a solenoid problem every time. It is easy to check, just unplug the little switch wire from the solenoid and put the battery cable back on. If it still turns, it's not the switch. If it doesn't turn, put the wire back on and try it before replacing the switch, since the solenoid sticking frequently resolves itself. Good luck, Mitch
I removed the starter and had it tested at a reputable auto electrics shop. It checked out fine, no problem with starter or selenoid. The tech said a low battery can cause this however the battery seemed to be fine. He also said a bad ground can cause this. Any thoughts. Thanks
Have you reinstalled it and tried it? If it works you are good, he is right about a low battery and bad ground. They both translate to low voltage to the starter, which translates to high amperage, which will make the contacts in the solenoid stick. Once they break loose, which they have it it tests good, you are fine until you get a low voltage again. This is sorta normal. If you reinstall it and it runs steady again, it is a problem with the start switch or the wiring from it. My money is on it working fine now. Good Luck, Mitch
No, but I'll be doing it soon. It broke down about 200 yards from the garage and it's 20 degrees out and we only have about 7 hours of daylight so it may be a few days before I can tackle it again but thanks for the info.
There is also a starter relay on the rear left hand side of the fire wall that some times sticks causing the stater to stay engaged when the key is off. Only disconnecting the battery cable makes it stop cranking. I have replaced a bunch of those relays for the same problem you are seeing.
That's a good thought, if it runs when you hook it back up, I'd go to that relay next. Actually, I wouldn't hook the starter back up, I'd take a test light and see if there's power to the switch wire to the starter, if it is, check that relay.
Yea there are two relays there one is for the glow plugs and one is for the starter. I believe the one to the left is the starter relay
Thanks NHtech01 I've tried all other suggestions but yours. I'll try that next. Thanks
NHtech01 you were right on. It got up to 27 degrees so I replaced the starter relay and it ran perfect. Thanks for the great advice.