Testing a Rebuilt Metal Coil Box

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1912touring
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Joined: Sun Jan 06, 2019 3:16 pm
First Name: Michael
Last Name: Hanson
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Testing a Rebuilt Metal Coil Box

Post by 1912touring » Mon Jun 28, 2021 12:39 pm

Good afternoon everyone.

I finished building a new metal coil box and switch this weekend for a 1916 engine. Is there a way to test the functionality of the coil box apart from installing it in a car?

I have verified the coils on ECCT. I want to make sure that the new reproduction switch and my soldering/wiring are good to go.

Kind regards,
Mike Hanson
Kingwood, Texas

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George Mills
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Re: Testing a Rebuilt Metal Coil Box

Post by George Mills » Mon Jun 28, 2021 1:00 pm

Take the front switch plate off...

use a continuity tester (cheap voltmeter from the parts store set to high ohms)

Remove coils...

One lead on the bottom copper strip...

Other lead on one side of the contact arc bar in the switch housing...

Flip switch....it should cycle the needle to full or zero with each flip...

Move to other side contact bar arc....

Flip switch....same expectation...

Button it all up, should be good to go...

Be careful taking the front plate off the switch, the rotor wants to fall out :)


Topic author
1912touring
Posts: 171
Joined: Sun Jan 06, 2019 3:16 pm
First Name: Michael
Last Name: Hanson
* REQUIRED* Type and Year of Model Ts owned: 1910 Touring, 1912 Touring
Location: Kingwood, Texas
Board Member Since: 2011

Re: Testing a Rebuilt Metal Coil Box

Post by 1912touring » Mon Jun 28, 2021 1:20 pm

Thank you George!


Scott_Conger
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Re: Testing a Rebuilt Metal Coil Box

Post by Scott_Conger » Mon Jun 28, 2021 2:05 pm

You should also ensure isolation of the Mag post from the Bat post at all times in all switch positions

George's test will make sure something will work

this test will ensure you don't inadvertently kill your magneto

assuming you used care in the rebuild, this test is unlikely to fail, but if there is a problem, rectifying things would take a good bit of effort. Might just as well go the extra mile and check while it's painless.
Scott Conger

Tyranny under the guise of law is still Tyranny

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George Mills
Posts: 619
Joined: Sun Jan 06, 2019 12:32 pm
First Name: George
Last Name: Mills
* REQUIRED* Type and Year of Model Ts owned: 1915 Roadster, 1919 Hack, 1925 Fordor
Location: Cherry Hill NJ/Anona Largo FL
Board Member Since: 1999

Re: Testing a Rebuilt Metal Coil Box

Post by George Mills » Mon Jun 28, 2021 4:41 pm

Good point Scott!

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