SAAC Forum

The Cars => 1968 Shelby GT350/500/500KR => Topic started by: shelbydoug on August 01, 2020, 07:24:10 AM

Title: 12v yellow top coil
Post by: shelbydoug on August 01, 2020, 07:24:10 AM
I came across this offering on the CJ Pony website.

Can anyone here speak to the durability of this coil?
Title: Re: 12v yellow top coil
Post by: Coralsnake on August 01, 2020, 07:35:22 AM
They did have a melting problem, I am told it has been "resolved"
Title: Re: 12v yellow top coil
Post by: Royce Peterson on August 01, 2020, 08:29:46 AM
Indeed the ones being sold 15 years ago would immediately start leaking oil and then fail. From what I hear they are good now but I have never had any trouble finding a good original for my own cars.

Quote from: Coralsnake on August 01, 2020, 07:35:22 AM
They did have a melting problem, I am told it has been "resolved"
Title: Re: 12v yellow top coil
Post by: shelbydoug on August 01, 2020, 09:57:44 AM
Quote from: Royce Peterson on August 01, 2020, 08:29:46 AM
Indeed the ones being sold 15 years ago would immediately start leaking oil and then fail. From what I hear they are good now but I have never had any trouble finding a good original for my own cars.

Quote from: Coralsnake on August 01, 2020, 07:35:22 AM
They did have a melting problem, I am told it has been "resolved"

The originals were 9v. This one is 12v.
Title: Re: 12v yellow top coil
Post by: Royce Peterson on August 01, 2020, 10:16:01 AM
The originals run on about 11 volts with the engine running or while cranking. If you measure the voltage with the key on but the engine not running then you will see 9 volts at the coil if the points are closed.

Because the alternator puts out about 13.8 volts the coil sees about 11 while cranking. The resistance wire is bypassed during cranking. The battery voltage is about 12.5 volts before cranking but gets dragged down by the starter. This is why there is a resistor inline with the coil.

The reproduction coils work fine in the stock circuit. If some website somewhere calls it a 12 volt coil that's because it isn't a reproduction 6 volt coil which also have yellow tops for the 1950's era Ford products. 


Quote from: shelbydoug on August 01, 2020, 09:57:44 AM
Quote from: Royce Peterson on August 01, 2020, 08:29:46 AM
Indeed the ones being sold 15 years ago would immediately start leaking oil and then fail. From what I hear they are good now but I have never had any trouble finding a good original for my own cars.

Quote from: Coralsnake on August 01, 2020, 07:35:22 AM
They did have a melting problem, I am told it has been "resolved"

The originals were 9v. This one is 12v.
Title: Re: 12v yellow top coil
Post by: Steve McDonald Formally known as Mcdonas on August 01, 2020, 07:57:36 PM
I have about 6 of these that have failed, cleaned the rusty, crusty original and put it back in the car and it hasn't missed a beat since
Title: Re: 12v yellow top coil
Post by: Shelbypat on August 01, 2020, 09:47:36 PM
Happen samething to me. The repro run 15 min and fail. I bought a good original used and never miss for 12 years now.

Patrick
Title: Re: 12v yellow top coil
Post by: shelbydoug on August 02, 2020, 07:59:10 AM
OK. Thanks for all the posts of your experiences with both the original Ford and the repro. I'll save my money.

I've had my own run-ins with ignition coils. I don't need to continue down that rabbit hole.

I need to point out though a couple of things that are apparent to me in this discussion.



First, the original yellow top IN IT'S DAY was very suspect to lack of product quality. Perhaps that was ONLY because few understood why it was a 9 volt coil to begin with? I'm not going to analyze that?

My issue is getting the tach to read properly using a 12 volt coil, and the combination of CJ advertising his repro coil as 12v rather then 9v and looking original was a great sales hook on me at that moment.


Secondly, no posters have dealt with reporting that the repro failings have long been corrected. I'm not sure how anyone can do that except report that they bought one  within the last year or so and have no problems with it. No one has done that.



I do appreciate sincere efforts of posters attempting to help out. However, this is the hard part to say, many of you need to take serious writing courses on how to focus on and illustrate exactly what you mean to say?

Sometimes here I feel like I am stuck in a revolving door on high speed simply because you contradict yourselves, sometimes within the same sentence?

That simply does not help the specific situation.

For instance, you need to know and understand the difference between flammable and inflammable.  ::)
Title: Re: 12v yellow top coil
Post by: Royce Peterson on August 02, 2020, 08:17:35 AM
There was a period of time in the 1990's when I could go to any wrecking yard and take good used yellow top coils off every Ford product on the lot. They are utterly reliable. Never have seen one fail in spite of me trying all sorts of stupid stuff.

Ford advertised endlessly in the 1960's and 1970's about how Ford racing cars used the same yellow top coil that you could buy. This advertisement is on many of the magazine rear covers that I bought when they were new in 1967.

Title: Re: 12v yellow top coil
Post by: shelbydoug on August 02, 2020, 08:29:43 AM
Quote from: Royce Peterson on August 02, 2020, 08:17:35 AM
There was a period of time in the 1990's when I could go to any wrecking yard and take good used yellow top coils off every Ford product on the lot. They are utterly reliable. Never have seen one fail in spite of me trying all sorts of stupid stuff.

Ford advertised endlessly in the 1960's and 1970's about how Ford racing cars used the same yellow top coil that you could buy. This advertisement is on many of the magazine rear covers that I bought when they were new in 1967.

That was then not now. How does that help anything now?
Title: Re: 12v yellow top coil
Post by: Royce Peterson on August 02, 2020, 09:37:34 AM
Nothing has changed. A good used yellow top coil is still very reliable and easy to find for sale. JD Larson, Marcus Anghel or Don Rush or a number of folks restoring them and selling them on eBay.

Quote from: shelbydoug on August 02, 2020, 08:29:43 AM
Quote from: Royce Peterson on August 02, 2020, 08:17:35 AM
There was a period of time in the 1990's when I could go to any wrecking yard and take good used yellow top coils off every Ford product on the lot. They are utterly reliable. Never have seen one fail in spite of me trying all sorts of stupid stuff.

Ford advertised endlessly in the 1960's and 1970's about how Ford racing cars used the same yellow top coil that you could buy. This advertisement is on many of the magazine rear covers that I bought when they were new in 1967.

That was then not now. How does that help anything now?
Title: Re: 12v yellow top coil
Post by: shelbydoug on August 02, 2020, 09:39:49 AM
Sure Royce, but the title to the post by me was 12 volt yellow top coils. 9 volt are not part of the discussion.

Why do you keep interjecting that?

There is no point in continuing this discussion.