If the back emf from the motor is causing the problem, the bad
connection to the motor should have made itself VERY evident by now.

** Not true at all.


If it was mine, or if I had the transformer at hand, I'd have it apart
and analysed in no time. If the primary is shorted, I'd know, within
an hour or two of the failure..


** What is clear is that the primary has suddenly drawn a very large current
and that means there are SHORTED turns inside the primary.

Go away ******.


...... Phil