Hallo! I've been lurking here for a while but this is my first post. I have a Primus 96 which I bought in 1974, and must be one of the last ones made. I used it for occasional backpacking or cycling trips until 1980, when we switched to gas for touring abroad. My camping days are long over but I would like to use the Primus again for the odd picnic. I still have the gas stove but these days am concerned about the throw-away canisters, and in any case these pressure stoves are much more fun, not to mention cheaper to run. The main problem is that as you can see from the photos below the burner head sits much too low on the lipstick, and the flame is very yellow. Back when I bought it I didn't know any better, and thought that its relative slowness and yellow flame were because it was a roarer rather than a silent burner which is what I had grown up with. I imagine that as one of the last ones sold it was made up of mismatched parts. The very first time I used it the head jammed firm on the lipstick, and ever since then I have been unable to remove it. I have tried heating and quenching it as described elsewhere on the forum but with no success. You can see where the spigot of the burner head is slightly scratched from the pliers. However I'm pretty certain I haven't deformed the spigot as I was very careful and at my age (!) don't have the strength to do so. Kaw550red posted a method for an extractor made out of heavy brass but I don't have the metal-working tools or skills to make anything like that. Any suggestions? I think if I could get this removed and shimmed to fit properly (and replace some washers) the stove would work well, as lifting the burner plate with pliers results in a nice blue flame. Thanks for reading. I would love to collect these stoves but don't have the space. Instead I enjoy reading about their history and looking at other folk's photos. There is a fantastic wealth of information here. cheers! L
First off, WELCOME !! A 96 is what got me started in all of this. Beautiful little stove. You are definitely on the right track to remove the bell. What are you using to heat it?? I am just wondering if you need more extremes in temperatures. Somehow keep the lipstick cooler than the bell. Cool wet cloth on the lipstick and tank should do it. One other thing that's going through my mind ... if its been there like that for so long, there's a good chance that there might be some corrosion keeping it together. My favorite trick for corrosion is to heat the area up and touch a candle to it. The wax will wick its way in there ( much like solder will when doing copper plumbing ) and should help things quite a bit.
Try freeze the base of the lip stick in a block of ice, then heat the bell with a torch. If you do it upside down the bell might just fall off, maybe...
I see from thre marks on the bell corner that you have been trying to turn the bell with a plier. That way, the harder you squze the plier, the harder you squize the bell collar to the lipstik. To turn the bell, try a srewdriver trough the bell holes. All other suggestions about cooling the lipstik whilke heating the bell collar are perfectly correct, and the ice block enclosing tank and listik base worked more then once for me, but NON using pliers in the bell collar. Hoping to be of any help. Orsoorso
Some penetrating oil on the burner bell where it joins the lipstick could do no harm. I use Kroil, but Penetrol or WD40 or something along that line might work too. Allow the penetrant to work overnight, tapping lightly on the burner's outside where it covers the lipstick will jar the penetrant into even smaller crevices. When you get it apart and cleaned, apply some well shaken milk of magnesia to the mating surfaces of the burner assembly, it is a very good anti-sieze product. On small parts such as this I use a Q-Tip as an applicator. Post some more pictures when you get it apart and running. Gerry
Hi L! Why do you think the burner bell sits way too low? Judging from the pictures I cannot see that this is true. Well, my Optimus 96 has another burner bell (rather like the one from the 8 R), but the lip stick goes through it from the bottom about as yours. Also my 96 is slow, and yellow flames can have other reasons, too. Best regards, Philipp
Hi folks Many thanks for your interest and advice. I've been using a propane blowlamp to heat the bell, but don't know how hot is 'hot' and am afraid to cause damage. Also I found it difficult to heat just the burner head without the heat transferring to the lipstick. I can understand that using ice on the tank and lipstick would help but I don't have the facilities to set this up. All I have is a basic vice which isn't mounted on anything solid. I tried using a screwdriver through the base of the slots but it didn't budge and I was afraid of distorting the head - the brass is quite thin. I also tried penetrating oil overnight but it didn't help. I haven't tried candle wax, though. Pillepalle: there are various posts on this forum showing the recommended level for the burner bell, and which say that if the jet is too close to the flame plate then there is not enough oxygen getting through and the flame burns too rich. If I hold the flame plate about 1cm higher than it sits normally I get a nice clean blue flame. It was browsing on this forum that made me realise that my stove could be improved. Loco7stove has very kindly offered to sort it for me and having seen all the examples of his impressive fettling skills I'm looking forward to having it fixed.
Holding the flame plate about 1 cm higher means increasing both the distance jet plate and the distance burner bell rim plate. The latter indeed often improves the burning behaviour of a stove, however, I'd doubt that the former is necessary. Anyway, please let us know how your stove performs after the treatment by an expert. Regards, Philipp
I was going by posts like https://classiccampstoves.com/posts/132765 ]this[/url] by Kerophile: It will be interesting to see what happens - I'm just about to send it off to Loco7stove.
Hi Margaret & All Well i managed to get the bell off of the 96 vapouriser using a large propane torch , 4 foot pry bar , some TNT & love The bell was far too large for the vapouriser it came with ( so much for Q.C. ) . So i asked Margaret if it would be ok to swap with one of mine to get a better fit & this is how it looks now 8) Next job was to test the new setup to see if was going to work & i think i've cracked it First a standard 96 plate Then an Optimus 100 plate 8) This looks ok & ready to return Hi Margaret , I hope this is what you wanted Best regards Stu
That is absolutely fantastic!!!! Thank you so much for doing this - I hope the roof is still on your shed after using the TNT ! I found this on kaw550red's Optimus history thread: Explains it all, I think. Again, very many thanks - it seems almost insulting to say 'well done', but I am really impressed!
Hi Margaret Just glad to help , shout you tomorow as i'm off to bed as i've got an 04.00 start in Norwich for my job on the railway Stu .
The burner parts arrived back from Stu yesterday and I fired it up - it worked like a dream, with a beautiful blue flame, and for the first time ever it got red hot . Unfortunately my camera battery had run out. Today it was too sunny to show the flame properly but I'm posting these anyway. I couldn't believe how quickly it boiled a pint of water - less than 5 minutes (after initial priming) without a windshield on a crisp day, and not pumped up to full power. (I did have a lid on the pan.) I am really really grateful to Stu for giving this stove a new lease of life. When the weather gets a bit warmer I will use it to 'drum up' a brew on a bike run. There is a classic example from 1971 here, about 2mins 45secs into the clip. [media=youtube]dahGaL6ehjc[/media] I'm not as hard core as that myself, though!
A better flame shot . I'm using the Optimus 100 burner plate from Stu which gives a more even flame and a better spread than the original.
