I just looked at a job this afternoon (here we go again).  A local,
self-proclaimed expert was perplexed that his second attempt at
rebuilding the secondary valves produced more of a problem.  I pulled
apart three valves to examine the pouches.  The first one had some kind
of rubber: elastic, but it tore easily.  The second had a paper material.
The third made me laugh, and the owner cringe -- plastic wrap.  No
kidding!

Of course the white glue didn't adhere well to the plastic, or hold on
the thin cardboard disc; it looked like cereal box material.  Perhaps
more vacuum leaked from under the fiber disc used as an inside valve
face.  I wonder why nothing worked?  Maybe it was the loose elbows.  Or
the glue which squeezed onto the pouches upon assembly.  Excessive valve
travel and pouch clearance also contributed.

I am not certain if I want to salvage these blocks, since I do not trust
the inside valve seat insert he put in, and the white glue joints will be
a nightmare to open.

Is there an orphan set of valve blocks out there?   I could get them from
a spare unit I have, but then I won't have a complete unit.  And what's
the going rate for these blocks?

The whole thing started with loss of vacuum to the treble.  This inept
imbecile flat-out told the owner, "It's the valves".  I inspected below
and found the expression mechanism loose.  That would have been a good
place to start.  One redeeming feature: the guy has a great view of a
lake.

Marshall & Wendell upright Ampico A, circa 1924.  All pneumatics were
recovered about 15 years ago which appear to be fine, a very neat job.
The valves were not done then.

It's a big job, but someone's gotta do it.  Special thanks go to John
Tuttle for my listing on his web page.  (I wish the guy looked there first
instead of falling for the hype in the Yellow Pages).

Jon Page
Harwich Port, Cape Cod, Mass.