2 stroke hover mower engine wire query

[Desmac]

I have two 2-stroke petrol hover mowers; a Flymo contractor L50 and an Allen something. both use identical Techmseh MV100S engines. The Flymo has a setting on the throttle lever which grounds a wire from the magneto to the engine block. This stops the engine.
The Allen has the cable grounded to the engine block to allow it to run (via a dead man switch). Can anybody through light on the purpose of the wire from the magneto which has seemingly opposite effects on seemingly identical engines?

[Mick]

Hi Desmac, and welcome to TGMF.

Both those engines use the same method to stop the engine.  A terminal on the ignition coil, once grounded will kill the spark.

Method used to achieve this vary slightly with different machines / engine combo's, but the principle remains the same.