I have restored two Weber grand players, one works perfectly but the
other will not play.  I have tried all parts on the piano that will
not play on the working piano.  The working piano plays regardless of
which components are on it.

The only difference I can detect is that the non-playing piano (it
tries to play but cannot) produces no vacuum from the primary box in
the rear of the piano to a control box marked AA on the schematic to
the left of the keyboard. The pump produces 60 - 70 inches of vacuum
at the Theme and Accomp. pneumatics.

It is almost as if it were hung up between play and reroll (it tries
to play in reroll same as in play).  All the other functions work
(reroll, repeat, tempo, and auto shutoff.)

I an at my wits end to straighten this out.  Any thoughts about this
strange behavior would be greatly appreciated.

Danny Wilson - mechanical piano lover