Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Good morning from Brooklyn

  Yes, that curved plate that goes over/around the trunion screw
is a real PITA.  I have two 90's, one I intend to customize,
so I cut that curved-portion off to make access easier.  Some
might say it is a sin to do so but I have to please only myself.

  So, the only way to describe how the trunion screw/spring should
be adjusted is, keep trying till you get it just tight enough to
run, and no more.  Running it on air while doing this will avoid
burning yourself on the hot metal.  Get it right, water it up,
plug it in, and away you go.

Good Luck,
Wayne