I have noticed on my upright Ampico Marshall & Wendell that the spring
on the relief valve on the pump body has a lot to do with the rewind
speed.  By loosening or tightening the tension on the spring the rewind
speed (and perhaps other functions while in the play mode) will be
affected.

The valve can be loosened by rotating the spring, without removing the
pin that holds the spring.  It is difficult to replace the pin through
the wooden holder.  Pulling the spring to separate the coils makes it
easier to shove the pin through the coil.  But avoid that if possible.

Bill Chapman
In Sunny Buffalo NY, concluding a great AMICA Convention

  [ Two busloads of AMICA people came over from Buffalo to North
  [ Tonawanda Sunday for the COAA Band Organ Rally on the Wurlitzer
  [ grounds, where I was able to meet some AMICA friends including
  [ our MMD Editor, Robbie Rhodes, who was at the convention on
  [ behalf of Jody Kravitz and himself to accept an AMICA award to
  [ the MMD for its service to Mechanical Music.  Now I am back home
  [ in Irondequoit, editing a late MMD this Monday morning.
  [ -- Relief Editor.