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I have this 1978 B&S Generator (M: 326435 0296-01) that I unbolted off of a trailer bought from a scrapyard. This thing was all rusted and beat up, and clearly didn't run, but I wanted to see if there was any way to restore it.

First I removed the flywheel cover and the engine cover and blew out all the debris: the leaves, mud, and rat nests that clogged around the flywheel. I checked the spark plug, and it seemed to be in decent condition. It looked like It was replaced recently.

I then tested the magneto. That thing was rusted and honestly looked terrible. I pulled the flywheel a few times, but there was no spark coming from the spark plug. I also pulled a few times with my hand directly over the spark plug, and there was not even the slightest shock.

So I figured the magneto was bad. After taking the old magneto to a local engine parts store, and ordering a new one, I attached the new magneto, and made sure to leave the gap between the magnet at .010".

Thanks to the electric motor mounted to the side of the engine, and geared flywheel, I hooked up a set of jumper cables from a lawnmower battery to the motor and was able to engage the electric start. I grounded the end of the spark plug while connected to the magneto, and flipped on the electric starter hoping to see a spark. And there was a spark... Well, kind of. It was a very inconsistent spark, and would sometimes spark and sometimes wouldn't.

I have read multiple forums where people suggested checking the strength of the magnet, as a weak magnet would produce a weak spark. I'm not exactly sure what is weak or strong though. My magnet will attract the end of a screwdriver from 1" - 1 1/2" away.

Then I read that this issue could be the condenser. But... after removing the flywheel, I realize that there is no condenser—or if there is one, I have no clue where to look. I was assuming that If it had one, It would be behind the flywheel. But I didn't see any cover or anything to unbolt.

I took a bit of fine-grit sandpaper and sanded the rust off of the magnet, hoping that would make a difference. It didn't.

If this helps, I also cleaned out the carburetor thoroughly, removed the crud from the combustion chamber, drained and replaced the oil, replaced the air filter, and fuel line.

I have repaired many small engine fuel problems before, but this is something I don't have as much experience with.

If anyone would give me some pointers, I'd be appreciative. Everything looks great internally, I just can't figure why the spark is weak.

Thanks.

The points and condensor would be external on that engine. Most likely on the side of the block under a rectangular cover for the points, with the condensor mounted close to it.

Are you talking about this? I did take that box off but it didn't look like there was any condenser. There is this plunger that sits behind that red rubber cap, I don't know if that is anything.

Looks like somebody has converted the points to an atom module. The points should be disconnected and there wouldn't be a condensor at this point Do you have a picture of the new module. I am just thinking the new module could have the electronic module built in and you no longer need the atom module. or anything on the side of the engine connected to that point box.

By module, are you talking about the atom module? I didn't replace it or have a replacement. Are you suggesting that the atom module needs to be swapped out with a new one? Or are you referring to the magneto or something?

The module could be bad, replace it if suspect.

I wonder if a standard Briggs coil with the built in module could be found that would fit (or could be made to fit) the mount on the old motor? Sure solve a lot of problems if so..

tom3 said:

I wonder if a standard Briggs coil with the built in module could be found that would fit (or could be made to fit) the mount on the old motor? Sure solve a lot of problems if so..

Click to expand...

I wonder if the 398811 will work. It is for the after 81 cast iron block engines even though his is the before 81 engine.

This is the coil I currently have attached. So you're suggesting that I should try the 398811 model? Since this ignition coil will replace the points and condenser, would it guarantee a better spark?

Thanks for the input. I really appreciate it.

I don't know if it would give you a better spark, but I am also thinking that your module is installed backwards. Need to take it off and turn it over.

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?

TheSensibleHuman said:

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

Click to expand...

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.

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

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.

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?

One of the wires goes to the atom module.

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.

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.

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 .

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

Either you have to have the atom module or a set of points and a condenser.