I have 2 of these l'il beauties; one has a brass pump rod and the pump knob is removable, the other is a steel rod and the knob is NOT removable. What's the supposed difference? Age? Was it a botched fettle?AKA cross threaded knob on a steel rod.
The 3 00's I have all have steel rod's but have a number of differences. One came in a plain red tin which I assume is the most recent. The two others are in the standard blue tin (one of which has very little paint left on it at all), but each has different methods for retaining the reserve cap, one screws onto the end of the pump knob and is round knurled and the other has a tank boss and is plain hexagon nut shaped, which I assusme to be the earliest. Whether this helps anyone who may be trying to date Optimus stoves or not I don't know. Simes
HI Hobo - I reckon the unremovable knob will be just seized. I checked all four of my 00's which span sometime before 1918 to the early 1950's & they all have steel pump rods. I have brass rods on a couple of Opt 96's, 22 & 111 & steel rods on an old 1S, 11, 100, 9 & a real early 96. I have some other models & scrappers in the garage I haven't checked yet. One thing can be said - it doesn't look like an example of later day cost costing.