Posted for randy snarr <randylsnarr@yahoo.com>:

 Gary,
 I too sent my pump back to have the thing checked and
 rebuilt as it was nearly 17 years old and never been
 used.
 They charged me $120 or so as I recall and the thing
 acted much better when it came back. I am assuming due
 to the spool vale being turned around.
 
 Did I need to say "install the back pressure mod"?
 I do not believe I did?
 Is that something they would have done as a matter of
 course?
 
 Maybe that is my trouble...
 
 Randy.