Ended up having three. Anyway, I had the luxury of a second one of these and tried the pull start assembly on it and it was quite smooth. That means something on the original mower is wrong. I hadn't thought of the flywheel key, must be onset of alzheimers. That is a good suggestion as the symptoms are like that. Strange though that it starts and runs OK with a drill or the odd pull with the cord. I guess that could mean the key has only shifted marginally. Does that sound feasible? The original is on the right.
[Linked Image]