Remove the spark plug and be sure the engine will rotate. Then follow the positive battery cable to the starter solenoid, touch the cable connection to the small switch post using an insulated wire, the starter solenoid should engage and the starter/generator should spin the engine. This checks the battery, cables, solenoid and the starter generator. If this all works, then you have a problem between the key switch and the solenoid. Here is link to the wiring. -----------http://www.cunninghamgolfcar.com/images/document/wiring%20diagram%20Yamaha%20G14A.pdf
Forgive me but I am struggling with your instructions
The positive battery terminal goes direct to a relay there are two leads at the point of connection one is the heavy duty lead from the battery and the other is a thin lead heading off somewhere else. another heavy duty lead then proceeds from the relay to the starter. what is meant by the small switch post, exactly. Just touching that with a insulated wire. unconnected to anything? How does that work? I think I understand you to be saying that I link the positive HD cable where it connect to the starter to a small switch post - if only I knew what you mean by that. Can you elaborate?
I have tried that and nothing happened. The battery is good as the wire started to warm. is there something about my cleaning the engine which is relevant or is that merely coincidence?
I did turn the engine via the flywheel and there was no problem.
take jumper cable direct from the battery to the starter/generator and see if engine will spin. If not, you know the starter is bad. Negative to the frame of starter, posiitve to the battery post on starter.
This has established that the starter/generator is functioning as it turned over the engine.
That sounds a good deal less expensive and probably nothing to do with my cleaning. Is it as straightforward as remove and replace as is?
Many thanks for all your help.