Thread: Dead Batteries
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Old 04-08-19, 01:03
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Wayne Hingley Wayne Hingley is offline
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Join Date: Aug 2015
Location: Water Valley, Alberta
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Default Dead Batteries

Due to a slow drain-down my M38A1 CDN2 batteries, Iíve become used to disconnecting the batteries if Iím not going to use it for a week or more. Iíve been using the Jeep a fair amount this year, and Iíve noticed the time to completely drain the batteries dead had decreased to 1-2 days. Now the batteries arenít just low, but completely dead.

Chris V. had mentioned that he found a couple of different shorts in his wiring system that took a while to diagnose, but once repaired all was OK. So last night I got the multimeter hooked up and started disconnecting and reconnecting circuits and watching for continuity variations. I also visually inspected the entire wiring harnesses as much as possible. I even pulled the ignition switch to see if it was failing. No luck finding anything.

Today I explained the situation to Rob L. and asked for his thoughts. Rob recommended pulling the starter out and checking the switch for fine dust and copper particles that can cause a drain even while not in use.

So I pulled the starter and found a fair amount of dust inside the switch. I cleaned and polished up all contact surfaces and reinstalled. See photo of what it looked like when I opened it up. There was also some very light smoke stains from arcing visible, so I think this may have been my problem. With the extra use I have been giving the Jeep this year, I think the copper & dust finally got to a threshold in the switch that was killing my batteries.

Iím monitoring the batteries now to see if there is any drain... hopefully that was the issue (fingers crossed).

Thanks for the help Rob & Chris.
Attached Thumbnails
1953 M37 CDN
1953 M38A1 CDN
1967 M38A1 CDN2

Last edited by Wayne Hingley; 04-08-19 at 01:06. Reason: Add photo
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