Scott's 1642 starts turning over when attempting to jump start with key removed.

wolf865

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Strange situation today. Wife could not get the mower to turn over even though battery read 12.47 volts. She suggested we try to jump start anyway? When we connected the jumper cables to a spare car battery the mower immediately started turning over even with they key in the off position and when removed? Engine was flooded so it wouldn't start but would the starter have even disengaged had it started, my guess not. We replaced the solenoid about 3 years ago. Any ideas on where to start troubleshooting? Key switch, solenoid again, other? Having a hard time finding search results on Google or Youtube when describing the situation. Help would be appreciated.
 

bertsmobile1

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Where did you connect the jumper leads to ?
 

wolf865

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Ran jumper cables from the spare battery to the battery still connected within the mower like I've done a dozen times before. Positive to positive, negative to negative. As soon as I touch the positive post on the external battery it tries to start. Key in the off position.
 

bertsmobile1

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Pull the control wire (s) off the solenoid and see if they are live when you connect the jumper.
IF the engine cranks with the control wires removed then the solenoid is jambed on ( never seen this happen before )
If the engine does not crank with the wires off then your key switch is bad or there is a short some where energising the solenoid, also rare.
IT would be really helpful if we know which engine is in your mower
 

wolf865

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Engine is a Kohler Command 16. Just changed the oil in it but don't see that would have anything to do with it. Drove fine from the garage to it's storage location under the house after that.
 

StarTech

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Remote starter solenoids can and do jammed in the on position. Especially when overheated from long starting periods.
 

wolf865

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
This just gets stranger the more I screw with it. Clamped onto the loose battery cables (not connected to original battery) with jumper cables yesterday morning and it cranked with the key just like normal! Hooked the original battery back up and nothing happened. Seems that sometime overnight it had drained down to less than 6 volts from being hooked up so took it out and put it on the charger. Tried to replace the solenoid but they mounted it in such an usual way I couldn't get to the torx screws to remove it. No good Google/Youtube suggestions on how to remove it. Guess I will have to rip it out and find a more serviceable way to remount it? Took connections off old solenoid and hooked it up to new solenoid (which I just set in there in contact with bare metal) and tried jumping it again, nothing, maybe a grounding issue.. Hooked wires back up to old solenoid and hooked the jumper cables onto the loose battery cables and it again started right up. Put the original battery back in after charging and again it started right up as if nothing was wrong. Wife came how and mowed, starting and stopping it several times without any problem. Looks like it might have corrected itself but this morning will tell more when I go down to see if it will start after setting overnight. Guess my wife is going to have to wait awhile for a zero turn mower replacement, this Scotts is 20 years old now. Called several John Deere dealers about the problem to see if they had a definite idea on a part replacement. Their only suggestions were that it might be the solenoid or starter switch? It was like they had never heard of a mower cranking without the key in the proper position. Surely I'm not the first person to have had that happen?
 

Gumby83

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Try wiggling the key in/out, up/down, and side to side while it’s in the ignition switch but in the off or run position (engine off). Could be an intermittent connection/short in the switch.
 

wolf865

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
Ran down to check out the mower this evening and it started up without any hesitation? Does it again I'm just going to rip out the solenoid and find a better more serviceable way to attach the new one. $14 isn't much a repair cost if that was, or becomes the problem again. Would still feel better if someone could say definitely what caused it to act the way it did. Happy mowing, the grass if growing! Actually it's the weeds on my acre of ground, but at least most of them are green.
 

Gumby83

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  • / Scott's 1642 starts turning over when attempting to jump start with key removed.
As others have pointed out, the solenoid must be receiving power with the key off to be engaging the starter - known as a short to voltage. If you understand how a basic relay works, the solenoid functions in the same way, so it must be getting power from somewhere in order to close the contacts.

Given the intermittent/odd conditions you’re seeing, I’m leaning towards the key switch or the wiring harness being damaged. You can use a test light in place of the solenoid to troubleshoot the key switch and harness.

I get your frustration with the solenoid location - I had a 1642 for several years and I didn’t like it either. I only replaced mind once, but when I did, I cut notches out of the bracket so that the screws only had to be a little loose and the solenoid could be slid underneath the heads. Then the screws only had to be tightened down a few turns - made installation much easier.
 
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