Found this Optimus on an auction. It appears to be the last version of the 350cp and has the 2-piece burner/frame assembly. The jet has a “3” stamped on the side. The air gap was set at 17.3mm. This is more than what I am used to with other lanterns being in the 13-14mm range. What is the correct gap? The vaporiser is branded “Petromax”, is this strange?
That certainly looks like the last variation of the 350cp. Even a bit of a transition version with that wheel. Just a 3 stamped on the jet is typical of the original Optimus 300cp jets. A Petromax vapouriser is unusual, but it looks to be the right size. The air gap should be as you mention at 14mm. I have found that these work better with a 200/250cp jet as all the burner parts are the same dimensions as the Optimus 200.
Thank you Nils. What I know I have learned from you! I will check the vaporiser of my other 350cp model (older or first version) tonight. the region where this was found (West coast of Namibia) and how long it has been sitting makes me confident that the lantern has not been tampered with or had parts replaced.
My older 350cp has an Optimus vaporizer so this one with the Petromax vaporizer is unusual? I have also converted the older one to a 200/250cp jet, it still runs hot but a lot better.
I can only agree with you there. I would not expect the lamp to have left the factory with a Petromax branded part. Would Petromax parts be more common to find in Namibia back in the day.
Namibia was a German colony at the turn of the early 1900's. Petromax lanterns are quite freely available here, but mostly the 1960's onwards models. I have found numerous Petromax 821 (250cp) lanterns from the 60's here, including a 250cp model with the "Sicke" fount. I have found one that is from late 1940's to early 1950's, however. The Optimus 930 lantern overall has not seen much use and I don't see why it would have required a vaporiser replacement at some stage?
Maybe someone just didn't know how to use it properly, tried changing the vapouriser with no success and it ended on a shelf. All speculation of course as we will most likely never know.
