[ Ref. Allen Scott in 210708 MMDigest --

Standard secondary valves are definitely an issue. I have a question.
Did you replace the lead tubing and and possibly the leather gasket on
the back board that the lead tubing feeds to? 

It has been said before, and I see the logic, that the lead tubing leaks
just enough to allow the primary valve to slightly rise, not enough to
cause a note to play but enough to allow a slight amount of air to seep
under the secondary valve pouch to slightly inflate it and push the
secondary valve off its seat. This seep could also be coming from the
back board gasket.

To test if this is the problem, remove the very top board. Unscrew the
back board and remove it. Using blue painters tape, seal the back and
test to see if your valves rise. If they don't rise, your problem was
above the taped off area.

Was the tubing replaced? Was the gasket replaced? Were the back board
screws tight? If the secondarys are still acting up then good luck!

Are the bleeds themselves clean and not plugged up? Did you replace the
leather gaskets between the primary chest and the secondarys? Are those
boards screwed tight?

One more stupid question. Did you replace the pneumatics deck gaskets?
It's possible that even though the leather looks and feel good, seepage
can occur such that outside air leaks through the screw holes and into
the valve chamber and overwhelms things.

To test if that is an issue, test the system without the pneumatics
attached. Put a small dot of tape over the exposed screw holes. You may
need to make a guide block that allows auction to the primary chamber
but so it goes. The very top deck usually does this job, but you will
be removing it for the moment.

Keep at it and good luck.

Jeff Davis, in overly sunny Seattle