Many thanks to Larry Norman for his input; over here in the darkest
depths of prehistoric UK we've obviously never heard of such a thing
as a thermometer, and who is this Scotsman he speaks of?

Seriously, how can you apply a set range of temperatures to analyse
weather a motor is working correctly or not?  All motors perform in
different ways -- some run very hot and some run cold.  I had dealings
with a 5 horsepower Century motor (repulsion/induction) which would run
all week and barely get lukewarm.

So, without having a technical specification for a particular motor,
you have to rely in the first instance on common sense.  If it runs
warm or hot to the touch over a reasonable period, but doesn't smell
like PCBs cooking, then it can be assumed that all is well.

Finally, if we are going to apply scientific apparatus to solving our
queries and problems there would be no point in discussing them on this
forum.

Cheers.
Paul Camps