What am I missing?

[Buddy Harley]

I have sucessfully got my model engines running with a old chevy points and coil system but now I need to scale it all down a bit. I can eleminate the points with a Hall Effect trigger. And I am useing a automotive relay for a buzz coil (works very good) But the problem is the coil. I have tried a motorcycle coil and a Mercury outboard coil but alas no fire. The have a pos/neg posts and an outlet for the sparkplug. I wired them just as if they were the old chevy coil. The system I am useing throws a blue spark almost an inch and with the buzz for as long as I want while the points are closed. The major problem is that although I understand mechanics very well, electronics are a dark place into which I dare not tread lightly. So if it don't 'bolt up' I am lost.
The system I am using has 12V battery pack and an internal resistor coil two items I want to stay with if possable.
Why are the other coils I have not working? (the mercury coils are the size I can deal with.)

[Elden DuRand]

Maybe this will help some.

http://home.cybertron.com/~edurand/O...0Pictures.html

Take care - Elden

[Buddy Harley]

While I understood some of that. It didn't explain why the coils I mentioned wouldn't work or at least I didn't catch it. There is a condenser in the 'chevy' type system and with that system I am getting plenty of spark. However when I try to insert one of the other type of coils there is no spark. All I need to do is get a smaller coil in the system that will throw the same spark as the chevy coil does.

[Elden DuRand]

Originally Posted by Buddy Harley

There is a condenser in the 'chevy' type system and with that system I am getting plenty of spark. However when I try to insert one of the other type of coils there is no spark.

Buddy:

If what I'm reading is what you meant to write, your problem is that you're not using a condenser with the other two coils.

All point-type high-tension ignitions must have the condenser across the points in order to generate any more than a puny spark or severely burn the points.

Take care - Elden

[Buddy Harley]

I was useing a condenser with the coils. In talking with someone, the motorcycle coil may not work because the type of ignition system some of them use sends high voltage to the coil via some sort of magneto thing. Ok, their too expensive anyway. However the Mercury outboard coils should have worked. I talked to a gentelman at MJN Fabrication and am sending him one of the Mercury coils for further exploration. I will also be trying a CDI system he offers as I was planning on useing a Hall Effect system sooner or later anyway. If that system preforms satisfactorly then I will only have two engines that have points systems and may just have to find a way to hide the chevy coil.