[jbrewer]

I've seen this comment many times in various places in this and other forums. The thing that puzzles me is that transformers/inductors are very efficient at what they do and aren't lossy (at least compared to other electrical components).

So... I googled to find an answer, and what I found doesn't make a lot of sense:

Like any other electronic component, excessive current flowing through the ignition coil may cause it to overheat. This occurrence is due to the spark plugs and wires having more resistance than anticipated, resulting in a voltage-current overload on the ignition coil.

I get the Ohms law heating especially since the wire gauge is likely very tiny in order to get the higher voltage on the secondary by lots of turns of wire. But "spark plugs and wires having more resistance" doesn't make sense to me in coil heating. And "voltage current overload" sounds like something AI would write. When voltage is high, current is low, and vice versa.

Higher voltage doesn't cause heating, and higher resistance doesn't cause "current overload" , but in fact does the opposite.

The position of the coil in a cub is pretty ideal... it's down low away from the cylinder temperature. In a typical V8 old car, it's on top of the engine near water jackets (hot) and, well...heat rises.

I'm not saying coils don't get hot but just curious as to why they seem to cause (or be blamed for) so many problems in our garden tractors. Is it just the DC current in the primary causing the heating? And if so, why is there no resistor block as in older engines to limit the primary current and in turn keeping the heavy IR drop outside of the coil? Resistors are much cheaper than transformers :-)