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Discussion Starter #1
can you guys direct me to a source for the electronic ignition for my B43M? I found a place called Kirk, but he only had a super coil and something called a points saver. Dont really understand what that is though
 

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Dean, I got my electronic conversion local at a place that sells/repairs portable welders & generators. A several of the earlier welder/generators used the Onan motor. You use the same coil, the conversion replaces the points.
 

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I dont think Onan sells the conversion kit anymore

The points saver cuts the current going across the points to almost nothing so they last alot longer
 

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Discussion Starter #6
I dont think Onan sells the conversion kit anymore

The points saver cuts the current going across the points to almost nothing so they last alot longer
yes, every place I have looked says discontinued, if the points saver cut the current how could that help the spark?
 

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It helps the spark, because the points ( the switch to trigger the coil field current collapse) send a "cleaner" signal and the spark is more consistent and happens when it is "supposed to happen".

If you decide to upgrade the coil. it usually has longer field windings (more turns) to increase the spark voltage. The "better" coil would still have the same effect (to a lesser degree) with the "points saver".
 

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There is a technical paper on the kirkengines website. For some reason I can only see the full website if I use Windows Internet Explorer, the site does not fully load for me with my main browser, Firefox.

Points saver puts the current through an electronic transistor. The points are then used as a low power trigger for the electronic transistor. This makes the points last a long time. The hotter spark, per the website, comes from the faster action of the electronic transistor causing the field in the coil to collapse faster and this generates a higher energy for the spark.

The website does not mention dwell, but in general an electronic ignition could also have an advantage over the points here. The points dwell is limited to how long the points stay closed. This is a function of how fast the cam is spinning and how long the points stay open. At low rpm and specially while trying to start the engine (starter draws down the battery and there is less voltage for charging the coil which causes the coil to need more dwell time to fully saturate), the spark "could" benefit from more dwell then the points can allow. Electronic ignition can start charging right after the spark, which can be well before points have a chance to close, specially at lower rpm/cranking.

If you over dwell the coil for too long you can overheat it. So you need a "smart" ignition to take advantage of the increased time available for dwell. My guess would be that the kirk module is "dumb" or a fixed dwell.

PS: I am not an expert, this is all just stuff I think I learned while converting my old jeep to fuel injection using megasquirt. I do not run the points saver, but it is on my list of to-do's for my old tractors.

Brian.
 
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