Help making my buzzcoil circuit work with 2 ignition coils

Thread Starter


Joined Jun 26, 2017

I am restoring a Fairmont RK-B engine (2 piston , 2 strokes), both sparkplugs should fire at the same time, i am using this circuit : (falstad/circuit), it works fine for another Fairmont engine we have (1 piston, 2 strokes). I tried connecting another coil in parallel to the ignition coil , both coils produce spark , but it's not strong enough.

Do you have any advices?


Joined Nov 4, 2013
Ideally you use a dual output coil (two outputs, not one) or two single coils in series.

I have a old Fairbanks Morse 2 cylinder generator that works that way. If both coils are in parallel (As I acquired it) they have weak spark and burn the points out after a few hours of run time.
But once I put in series they both had good spark and never gave any further points issue either although ideally it should have had a single coil with dual outputs rather than two single coils.

As for the schematic you link to I too have no idea what they are going for being a properly designed points and condensor based ignition system only needs a single capacitor/condenser in parallel to the points. Adding more and too much capacitance elsewhere on the points side of the coil just make things worse.


Joined Sep 30, 2009