Left ignition switch ON

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Scott in NM
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Left ignition switch ON

Post by Scott in NM » Mon Feb 26, 2018 11:12 am

What are the ramifications of leaving the ignition switch on long enough for the batteries to be completely drained? Two things I can think of:
1. May need new batteries.
2. I heard some time back that this operator malfunction can burn out a coil. Can someone confirm?

Jeep won't start but cranks very nicely, assuming #2 could be the problem. Any other issues I should be made aware?

Thanks guys!

Scott


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Chuck Lutz
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Re: Left ignition switch ON

Post by Chuck Lutz » Mon Feb 26, 2018 12:37 pm

Check for burnt points....

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Then worry about the other components.
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dpcd67
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Re: Left ignition switch ON

Post by dpcd67 » Mon Feb 26, 2018 2:40 pm

Good luck because it's always bad. I had that happen on my M37 two years ago (idiot neighbor) and it cost me two batteries. Batteries Plus tested them and they were completely ruined inside.
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Re: Left ignition switch ON

Post by Joe Gopan » Mon Feb 26, 2018 2:58 pm

If you are lucky, it will just fry the points and not overheat and burn out the coil. look for discoloration of the contact points.
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Re: Left ignition switch ON

Post by JMZ421 » Mon Feb 26, 2018 4:51 pm

Please let us know what the fix was. The season will be starting soon and I am sure something like this will happen to me. Last summer while cutting the grass neighbor kidI( I think)pulled my fording handle, luckliy caught in time. John

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Re: Left ignition switch ON

Post by Wolfman » Tue Feb 27, 2018 4:38 am

Put a battery charger on the battery ASAP. Lowest charge rate and let it recharge over several hours. Long and slow is the secret.
If the battery was OK before, but now completely dead, the plates will sulphate, if left setting dead. Then it is toast.
One more thought. Be sure you get the charger polarity correct when connecting the charger. It is possible to reverse charge a completely dead battery. I have seen it happen. Positive becomes negative and negative becomes positive.
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Re: Left ignition switch ON

Post by Joe Gopan » Tue Feb 27, 2018 4:52 am

leaving the Ignition switch on has been going on in cars and trucks since battery ignition was introduced. Another event common to MV's is accidently leaving the BO Marker switch in "on" position, it will not affect Ignition components, but will drain the battery flat. This happens a lot when children (big children, too) are left alone in an MV.
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Re: Left ignition switch ON

Post by artificer » Tue Feb 27, 2018 7:21 am

Leaving the ignition on over an extended period can soften the point's return spring. This allows one start the engine & it idle OK, but on acceleration missing & breakdown occurs
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Re: Left ignition switch ON

Post by Chuck W. » Wed Feb 28, 2018 6:29 am

This is why all my MV's have battery disconnect switches and I use them religiously.

Scott in NM
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Re: Left ignition switch ON

Post by Scott in NM » Sun Mar 04, 2018 9:54 am

OK, fried the coil. All connections showed a short (no resistance). Frying a coil is one thing, easy and cheap enough to get a replacement. What chaps my hide is that I think it to be the original coil as the jeep came off the assembly line. That really hurts.

Points seem to be OK.

Thanks for your inputs and help.

Scott

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Re: Left ignition switch ON

Post by KiwiMB » Sun Mar 04, 2018 9:36 pm

To generalise:
If the points are closed when the ignition is left on, then the battery will ultimately drain via the coil, to the points and then to earth (ground).
The constant flow of current through the coil will over heat the coil leading to coil burn out. Fortunately the slow drain of the battery should not damage the battery (or batteries as the case may be.

There should be no damage to the charging system provided that the cut out relay in the voltage regulator is functioning correctly.
Its a real bummer that your original coil burned out though.

Cheers

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