Ignition Switch

1952 - 1968, M38A1, M170, questions, discussions, regarding anything related to the M38a1 series.
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vanzile120
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Ignition Switch

Post by vanzile120 » Sat Jun 11, 2016 8:50 pm

Need help replacing the number tags on my 1953 M38A1 original Ignition Switch. I have uploaded a picture. Looking at the switch from the back with the off position at 6 o-clock there's a row of three wires. The center wire has a single wire going into a dual davis connector. Can somebody out there tell me what numbers the wires are. This is the original switch and the original wire coating had worn off along with the number tags.
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Joe Gopan
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Re: Ignition Switch

Post by Joe Gopan » Sun Jun 12, 2016 4:02 am

Is that tape on those wires" The numbers do not wear off, they are supposed to have metal bands crimped to them at the connector. The Original 3 Wire "Potted" switches have a habit of shedding their insulation with age and can be dangerous as they also accumulate moisture as the switch ages, 10 years is enough to do it. Moisture/Age causes these switches to split open, I have seen these switches short out by themselves and fry the wiring harness.
The Circuit numbers to the switch are:
11 IGN SW to Light Switch "B"
12 IGN SW to Distributor
27 IGN SW to Inst Panel Spider
85 Auxiliary Wire (Heater, etc. it originally had a dummy Douglas Connector attached to prevent shorting.
I would suggest in the interest of safety to purchase the newer style switch with the four rubber sockets, the dealers have the correct numbered pigtails with Douglas connectors.

Best get yourself a TM9-8014 M-38A1 Operators manual, it has wiring diagrams and number codes.
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vanzile120
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Re: Ignition Switch

Post by vanzile120 » Sun Jun 12, 2016 4:37 am

Thanks for the reply. To answer your question, that is not tape on the wires. It is new rubber. I have the TM you speak of but it does not show the wires specifically. It just lists what wires are there as you have done. And I have a correction. My orientation is upside down. The off position is at 12 o-clock. I have the proper number tags, but when I re coated the wires, I failed to mark them. I will take your suggestion of replacing the entire switch but would like to try this one. So IM still looking for the wh

vanzile120
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Re: Ignition Switch

Post by vanzile120 » Sun Jun 12, 2016 4:37 am

Thanks for the reply. To answer your question, that is not tape on the wires. It is new rubber. I have the TM you speak of but it does not show the wires specifically. It just lists what wires are there as you have done. And I have a correction. My orientation is upside down. The off position is at 12 o-clock. I have the proper number tags, but when I re coated the wires, I failed to mark them. I will take your suggestion of replacing the entire switch but would like to try this one. So IM still looking for the which tag goes on which wire.


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