"""The connector in the engine can have solder joints crack usually on the outside and this effects motor and some times power. PS-1 had the same affliction. Also the wire inside the harness from tender can break."""
This is the dog that bit me on my MTH Hudson...
Cracked solder joints on the tether connector were causing it to either run away, or run very erratic (jerky motion). A re-solder on the joints and she runs like new now.
I think what happens over time is that tight curves puts additional stress on the tether and connector causing solder stress cracks, or possible open wires in the tether harness itself (even though an engine might be rated okay for 031 curves). I also think that if the tether harness wire is too short from engine to tender, this could be another stress point on the harness.
I never pull on the tether wire to uncouple/couple to the tender, I work the tether via the plug whenever I have to handle it...
