My Dora runs well, but I'm having trouble fueling it consistently. Some days everything works fine. Other days it seems as if there is back pressure from the tank against the butane can adaptor nozzle. Fuel squirts back as if the tank is full, but it isn't. Sometimes it's still empty. I can then use the same can, adaptor and nozzle on a different loco (or multiple locos) and everything is fine. I've been through this routine multiple times. I've changed the Ronson valve several times and made sure there is nothing in the tank or fuel line. I've also let a little fuel escape through the loco fuel valve for a few seconds and then closing off before filling up. Sometimes it works, sometimes it doesn't.
It seems as if the really Dora's small tank can't accommodate the pressure from the fueling system. I've used the same fuel for a year (Coleman). Nothing else has changed.
I'm not sure what to try next.
Thanks,