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If you are chatting about my post.
As I understand it, Bob's Jubilee was 6 volt, positive ground when he got it. A local tractor guy converted the ignition and charging system to 12 volt, negative ground replacing the generator with a GM alternator. The 6 volt starter motor was left in. Not sure about the lighting, I don't think they work anyway.
I'm guessing this is a popular conversion?
You also asked whether it needed an external resistor, and if it still has the original coil then yes it needs an external resistor. if it has a true 12 volt coil then no, it does not require an external resistor.

There are coils that are labelled "12 volts, external resistor required" and lots of folks argue that these are true 12 volt coils, but they are not. They are designed to be run in a 6 volt system with no external resistor or in a 12 volt system with an external resistor, and the label is a warning that you need the resistor in a 12 volt system.
 

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Discussion Starter #22
There are coils that are labelled "12 volts, external resistor required" and lots of folks argue that these are true 12 volt coils, but they are not. They are designed to be run in a 6 volt system with no external resistor or in a 12 volt system with an external resistor, and the label is a warning that you need the resistor in a 12 volt system.
Thanks Sean.
The replacement coil was labelled that it needed an external resistor, so we left it in. Seems to be running fine now.

Have a great holiday season.

Al.
 

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Discussion Starter #23
A quick update.
Bob and his missus were over for supper during the holidays. I asked him how the Jubilee was running, he said it was hard to start, but always has been, doesn't idle well and sometimes stalls. I realized that I had never checked the timing, so I headed over armed with my timing light. It was hard to start and didn't idle very well so I hooked up the timing light. Couldn't see any timing marks in the window so I shut it down and turned the engine with the fan blades - cleaned and marked the timing with a white paint stick, fired it up again - still no timing mark, turned the distributor (a lot) and the idle smoothed out, eventually the mark came into clear view, tightened the clamp bolt and called it done.
My point is, the timing was WAY out, if '0' is TDC and I had to turn the distributor a lot to get 9 degrees BTDC does this mean it was firing several degrees AFTER TDC?
Anyway, it now starts easily and quickly settles down to a smooth idle.
Have a great 2018.

Al.
 

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Discussion Starter #25
Good on you Al! Always warms my heart to hear of someones success in helping others.
Thanks DB - a warm heart is a good thing this time of the year (up here anyway).

I didn't pay attention to which way I was turning the distributor. One way almost stalled it, the other way it just got better and better. My, poorly worded, question was, as I had to turn the distributor quite a bit before the zero degree (TDC?) mark came into view then a bit more to the nine degree mark, does this mean that the engine was firing previously after TDC or WAY before.
"Inquiring minds need to know"

Thanks again.

Al
 

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It all depends on which way you turned the distributor, it was either way early or way late. Turning it clockwise retards the timing.
 

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It sounds like your timing was retarded or firing late, after TDC---when you turned the distributor you were advancing the time till you got to 9 degrees BTDC---you probably heard the engine smooth out and speed up slightly, Dennis
 

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Discussion Starter #28
It all depends on which way you turned the distributor, it was either way early or way late. Turning it clockwise retards the timing.
It sounds like your timing was retarded or firing late, after TDC---when you turned the distributor you were advancing the time till you got to 9 degrees BTDC---you probably heard the engine smooth out and speed up slightly, Dennis
Thank you both. Yes, I think the timing was retarded and I advanced it - makes sense! Now I can sleep at night.

Al
 

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I have a 1956 800 series with 6 volt positive ground, and I was having trouble with coils burning out. Make sure you have new points that are set set with the proper pap. After replacing coils, noticed I had slightly burnt points with a very small gap. Doing a lot better now and have not had a coil burn out in a few months.
 
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