The Ford Barn

Bryan Markell · 11-20-2023, 07:45 AM

Need correct spark plug and coil wiring for a Model A engine, may I ask who might currently be the supplier?

J Beard · 11-20-2023, 08:51 AM

I have used Brattons for over 30 years. For many of their parts they have options and will state which is correct and what is a modern option.

Joe K · 11-20-2023, 08:58 AM

The spark plug are the copper or brass "jumpers" that go between the nubs on the distributor cap and the screw top on the spark plug. Any jumper will work but earlier cars were one pattern, later cars another.

The "hot" wire between coil and distributor top is available from suppliers. Originally without "hoods" or caps, many users put a modern rubber hood to "seal" the connection against entrant water.

Otherwise, coil wiring would be part of the "harness" which most every Model A supplier will sell you. And this would be separate from the headlight wiring which is sold frequently with the "switch plate" - and have quality issues all their own.

Wiring diagram with correct wire colors below.

https://lesmodela.files.wordpress.co...ng-diagram.pdf

Sources of repop Model A parts with online catalogs below (Google search terms)
Tams Model A
Snyders Antique Auto
Brattons Antique Auto
Berts Model A

There are others.

Joe K

BRENT in 10-uh-C · 11-20-2023, 12:20 PM

Quote:

Originally Posted by Bryan Markell

Need correct spark plug and coil wiring for a Model A engine, may I ask who might currently be the supplier?

Bryan, before we go too far, ....define 'correct' as it pertains to your question. The two reproduction items that you are asking about are not "authentically correct" in all details as compared to original OE supplied pieces if that is your goal. It is the length on the spark plug wires, and the sheath on the coil wire that is the differences.

Bryan Markell · 11-20-2023, 01:20 PM

Thank you for the responses. With your help the question has been satisfied.

nkaminar · 11-20-2023, 08:22 PM

Sponsored Links (Register now to hide all advertisements)

I saw a photo of a Model A where barbed wire was used between the nubs on the distributor housing and the spark plugs. Is this original?

Joe K · 11-20-2023, 08:52 PM

Quote:

Originally Posted by nkaminar

I saw a photo of a Model A where barbed wire was used between the nubs on the distributor housing and the spark plugs. Is this original?

High tension corona dissipative discharge points.

Similar in effect to the top point of the lightning rod on your barn.

I have used a metal paperclip when one of the brasses went missing.

Joe K

Ray in La Mesa · 11-20-2023, 10:07 PM

It's not original but it works, it will bite you even when the engine isn't running! I have it on the #1 spark plug in my 86,000 mile '28 roadster pickup just to make people smile.

11-20-2023, 08:51 AM	#2
J Beard Junior Member Join Date: Oct 2023 Posts: 2	Re: Model A engine wiring I have used Brattons for over 30 years. For many of their parts they have options and will state which is correct and what is a modern option.

11-20-2023, 08:58 AM	#3
Joe K Senior Member Join Date: Jul 2010 Location: Cow Hampshire Posts: 5,019	Re: Model A engine wiring The spark plug are the copper or brass "jumpers" that go between the nubs on the distributor cap and the screw top on the spark plug. Any jumper will work but earlier cars were one pattern, later cars another. The "hot" wire between coil and distributor top is available from suppliers. Originally without "hoods" or caps, many users put a modern rubber hood to "seal" the connection against entrant water. Otherwise, coil wiring would be part of the "harness" which most every Model A supplier will sell you. And this would be separate from the headlight wiring which is sold frequently with the "switch plate" - and have quality issues all their own. Wiring diagram with correct wire colors below. https://lesmodela.files.wordpress.co...ng-diagram.pdf Sources of repop Model A parts with online catalogs below (Google search terms) Tams Model A Snyders Antique Auto Brattons Antique Auto Berts Model A There are others. Joe K __________________ Shudda kept the horse.

11-20-2023, 01:20 PM	#5
Bryan Markell Member Join Date: May 2010 Posts: 75	Re: Model A engine wiring Thank you for the responses. With your help the question has been satisfied.

11-20-2023, 08:22 PM	#6
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 6,856	Re: Model A engine wiring Sponsored Links (Register now to hide all advertisements) I saw a photo of a Model A where barbed wire was used between the nubs on the distributor housing and the spark plugs. Is this original? __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.

11-20-2023, 10:07 PM	#8
Ray in La Mesa Senior Member Join Date: May 2010 Location: La Mesa Ca Posts: 1,328	Re: Model A engine wiring It's not original but it works, it will bite you even when the engine isn't running! I have it on the #1 spark plug in my 86,000 mile '28 roadster pickup just to make people smile.

11-20-2023, 07:45 AM	#1
Bryan Markell Member Join Date: May 2010 Posts: 75	Model A engine wiring Need correct spark plug and coil wiring for a Model A engine, may I ask who might currently be the supplier?