Thank you for posting the link to the wiring diagram Rod, that should be a big help when we know enough about the symptoms to put them into a context.
Please go ahead with giving us the Model, Type and Code information for the engine, so we can find the Illustrated Parts List for it. Equally urgently though, I need to have a clearer idea of what is happening.
Is the starter motor being activated when the engine is already running? That would have an ugly effect on the starter mechanism, and the associated wiring. If the starter motor sometimes starts running without you touching the multifunction keyswitch, there is an electrical defect in the keyswitch or the wiring attached to it. Please clarify whether this is what you are telling us. The only reason I ask about the starter motor is that you have indicated that the starter motor operating solenoid (your last photograph) is somehow implicated. That solenoid has no function other than to operate the starter motor.
You said that smoke was coming from the armature. The item marked "armature" on the wiring diagram is the ignition module, of which you have posted photographs. That Magnetron ignition module has nothing to do with the mower's electrical system. Is the problem with the ignition system, or the electrical system, or both? For background, we have had cases before when some previous tenant (owner of the mower) has become inventive and improved the wiring by connecting the Magnetron's kill wire to plus 12 Volts whenever the engine is running. When this happens, the Magnetron soon burns out, possibly emitting smoke as it does so. The kill wire has only one function: to stop the ignition when it is grounded. When the engine is intended to run, the kill wire must be floating (that is, neither grounded nor connected to a voltage). In this case, it seems conceivable that the evil deed of rewiring the kill switch to the wrong terminal of the ignition switch, also interfered with the starter wiring.
Last edited by grumpy; 20/03/14 05:35 PM. Reason: Add detail
