The British Organ Blowing Company Limited has been around since the
early nineteen-thirties.  It currently operates as B.O.B. Stevenson
Limited.  They supply blowers and the like for industrial application.
Their URL is  http://www.bobstevenson.co.uk/about.htm

Although I suspect that your organ blower has outlived its guarantee,
I wouldn't be at all surprised if they still have the record of your
installation.  Dash off a quick note to them and I'm reasonably certain
that they will be entertained enough by your request to respond with
good advice.

Alternatively, stop by your local electrical contractor's supply house
and they will be able to test the motor and starter.  My guess is that
the motor is drawing too much current, either a short or fault in
kicking out of start mode.

Let us know if you can identify the source of the problem.

Bill Finch

 [ Ask the motor firm to test the old motor for shorted turns and
 [ shorts to the case (ground faults), and ask if they can provide
 [ a recommended wiring diagram.  They might suggest that your motor
 [ be fitted with a different (modern) controller, one designed for
 [ starting the motor when powered by mains of limited amperage.
 [ -- Robbie