I was asked to look at a Broadwood grand player piano at the weekend.
The piano was fitted with a Kastner player and was a very basic player,
having no sustain pedal and no automatic expression mechanism.

The player had ceased to function over a few months, some time ago.
On closer inspection, the soundboard had begun to show signs of cracks
appearing, although thankfully there was no sign of vibration.  A tuner
on his last visit had also commented that the pins were also not as
tight as they may be.

The whole player system seemed to be reasonably air efficient until we
get to the stack.  After this point pedals "turn to jelly".  My current
thinking is that the efficient heating system in the house and
combination of sitting in a warm bay window has dried out the pouches
causing each valve to be fixed open, and a subsequent massive suction
loss?  My questions then are

a) does this sound a feasible diagnosis?

b) I've been informed that the Kastner stack is not the easiest to open
and restore.  Has anyone tried this and are there any tips?  The only
one I've had so far is "Don't bother!"

Look forward to your ideas.

Mark Fudge