1978 Briggs and Stratton Generator Ignition Problem

[TheSensibleHuman]

Are you talking about the ignition module or the magneto/coil? I don't think the ignition module could be flipped. There's a step or groove in the bottom of the module, where the mounting screw sits. The module wouldn't sit correctly reversed I think.

Though, If you are referring to the magneto, is it possible that it could be reversed?

 

[ILENGINE]

Are you talking about the ignition module or the magneto/coil? I don't think the ignition module could be flipped. There's a step or groove in the bottom of the module, where the mounting screw sits. The module wouldn't sit correctly reversed I think.

Though, If you are referring to the magneto, is it possible that it could be reversed?

View attachment 52227View attachment 52232

I am referring to the magneto/coil which unfortunately is also called a ignition module. And in the picture it looks like it is reversed from how it should be.

 

[TheSensibleHuman]

Oh, thank you. Sorry for the confusion. I'll try reversing it tomorrow.

 

[Romore]

The only armature that will work on your cast iron engine is p/n 298968. For reasons unknown to me the aluminum engines have the flywheel polarity reversed so 398811 is not compatible. The factory did offer a free polarity change but the customer was responsible for shipping and handling.

 

[TheSensibleHuman]

So I unscrewed the magneto and flipped it around so the wire going to the spark plug was facing right but It's still not putting out a spark. Can anyone tell me if I'm wiring the wires correctly? Are both wires supposed to be grounded, or is one of them supposed to go to the atom module or something?

 

[ILENGINE]

One of the wires goes to the atom module.

 

[TheSensibleHuman]

After grounding one terminal of the atom module, I joined the other wire to the black wire coming from the magneto. When I tried to start the generator I placed my hand over the spark plug and felt a pretty significant shock. But apparently not significant enough since there still is no spark.

Does the atom module act as a capacitor and amplify the voltage?
Is there a way, should the module be bad, to test with a multimeter?
Is it possible to install a condenser? And do you think that would help with the weak spark?
Or do you think the weak spark could be caused by an incompatible magneto? The M/N for the new one I have is: 298968 so it should be compatible...

I'm trying to evaluate any potential options here.

 

[ILENGINE]

The Atom module works just like the points except is senses when the peak magnetic field is generated and then opens the electronic points which induces voltage into the secondary winding of the coil to fire the plug. It doesn't have any capability to amplify anything. And the only purpose of the condenser is to act as a voltage sink to prevent arcing of the points when they open. I don't know if they can be tested or not. Just haven't dealt with them much.

 

[bertsmobile1]

Illengine has it in one.
When Atom was selling their units as stand alone items they were sold as "POINTS ELIMINATORS" because that is all they were .
Over time the basic idea has been modified and a DIFFERENT PRODUCT became available called a capacative discharge ignition which is an Atom connected to a discharge capacitor which is conected to the coils.
That is what the diagram added to the previous post was .
I was going to point this out but closed the tab without thinking.
A CD ignition uses a different coil and is the same system as a car coil with the cap replacing the battery.
As this engine came from the dump, there is no reason to assume that any part on it is correct which could have been the reason why it was discarded in the first place .
The fact that you only get a spark when the flywheel is spun backwards points towards either the wrong coil , wrong flywheel or both

The original 2 wire Atoms have to be connected correctly and do not work if the coil wire is grounded so try it connected both ways .

 

[TheSensibleHuman]

Do you know if there is any way to start the engine without the atom module attached?