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

I use the old school Mamod spirit burner with the scuttle on with denatured ethanol. If you use Esbit, perhaps that may affect it? I've also noticed a lot if variance in engines...

I also used a meths burner with mine. My blue SW1 has a trunion spring that I believe is too tight. It is
Completely compressed when the bolt is fully tightened leaving the cylinder tight on the port surface. Also, I found
a tight spot in the cylinder. I lapped the piston in the cylinder so that it moves more freely but I feel I need to
shorten or replace the spring.