How are you checking for spark? That is a continuous loop system so testing is a little different. Do you have a way to connect two spark plugs together with spring clamps and a wire connecting them like is in the picture? Kohler recommends 4 spark plugs for this test. Two out of the engine connected to the plug leads and connected together via the metal hex area, and two left in the engine to keep the engine at normal cranking speed.
The attached picture is from a MV manual but they use the same ignition module as the M and are checked the same way. Current from the ignition module actually flows from the module down one plug lead, through the spark plug and block and then back to the ignition module through the other plug lead to complete the circuit in a continuous loop causing both sides to fire at the same time. On one side current flows from the module to the spark plug and spark jumps from the center spark plug electrode to the bendable electrode. On the other side the spark jumps from the bendable electrode to the center electrode then through the plug wire back to the ignition module.
