Hi All,  Somewhat concerned about the recent postings about PPCo's
Wurlitzer block valves, I called Durrell Armstrong and ordered six
units for testing.  While I had Durrell on the phone, I asked him about
the exhaust facings, intake facings, valve clearances and pouches.

Durrell told me that the new blocks are being produced with kangaroo
leather pouches, "sponge silicone" exhaust facings (not sponge neoprene,
as has been reported here) and patent leather intake facings.  Each
valve block is personally assembled and tested by Durrell.  (This was
a fairly recent change that was made when it was discovered that the
person in charge of making the blocks was not doing a good job.)

Kangaroo leather was selected for the pouches because it is much
stronger than tan pneumatic leather.  It also is more airtight than tan
pneumatic leather and just as flexible, if not more flexible.  Silicone
sponge was selected for the exhaust facings because it is the longest
lasting material available that has the required properties.  It will
not break down under any circumstances.  Patent leather was selected
for the intake faces because it is 100% air tight.

Regarding the valve clearances, Durrell said that if anyone found one
of his valve blocks with a clearance of over 0.040", he would gladly
replace that block at no cost.  The blocks being made now are set at
1/32" or 0.03125"

What surprises me most about some of the postings about PPCo's products
is that it's fairly obvious that some of the individuals who wrote the
postings never bothered to call Durrell.  Posting outdated and/or
incorrect information to the Digest does nothing of any value for MMD
members or the companies who work so hard to keep this niche industry
alive.  I'd suggest that authors check out their information before
writing to the MMD.

More later,

John A. Tuttle

 [ Nonetheless, MMD will continue to report history and opinions,
 [ favorable or unfavorable, about problems encountered and hopefully
 [ resolved.  MMD authors are encouraged to check their data carefully
 [ and to report errors, changes and new developments; I can't do that
 [ for you!   Thanks for the update, John.  -- Robbie