mantle becoming black, flames from the top

    I have my Petromax 500 for some time now, and in the beginning it worked reasonibly well. But now almost every time I light it up, orange flame appears around the mantle, sometimes the flames come from the top, and soon the mantle becomes completely black or with black spots, therefore rendering the lamp useless.
    The distance between the vaporizor top (spray nozzle) and the opposite tube (mixing shaft) is perfectly correct, according to the scale on the tool.


    Also I remember, when first burning the lamp some three years ago, the fresh mantle after the inital burning became totaly white. Now, it rarely gets perfectly white, and - already in the beginning - it has greyish areas. I don't know whether that contributes to the problem. Mantles are being stored in the original package, I avoid touching them, when I put them on, and I'm very patient with everything, but still these flames at the top, orange burning mantle turning black and also a flame out of the vaporizer top (spray nozzle) even some time after I turn the lamp off and I release the pressure. (I pressurize the lantern to 2).
    what could be wrong?
    is the type of kerosene (petroleum, paraffin) also important? does it matter if it's coloured when liquid (in my case green)? does it matter if it has higher (80°C - usually for stoves) or lower (35-40°C) burning points. I use both, and both make generally the same results...
    I once also changed the spray nozzle and the needle with the spare ones already supplied with the lamp, and the problems were the same as before, and also I have to say that the support bracket for the mantle turned out to be a bad idea, because it just crumbled after maybe 60h of normal work, when I tried to change the mantle. The heat destroyed it, which means it's quite useless, and not to use it, is from my experience good enough, it's just a shame 'two hole' mantels are more available than the 'one hole' ones!
    otherwise the lamp is not loosing pressure when not on. it sometimes starts to pulsate when it's running on low pressure, but I guess this is normal.
    thanks for the answer, after all this I'm slowly loosing my patience, fighting the flames and black spots on the mantles, which of course destroy them!!

    Woland,
    Hello and welcome to the forum. Flaming mantle and lots of fire usually indicate that the lantern is running way to rich. You said that you put a new nipple and needle in your lantern but did you make sure that the nipple was tight and is the needle adjusted to the proper height above the nipple in the closed 12 oclock position? The nipple has to be really tight to seal properly. I always put muffler mender on the threads of a new nipple and tighten it down well. You might think it is tight enough but it may not be. Not sure about colored kero?? I always use clear K1 kero in mine with no problems. Single sided mantles are what i use and not the double end type. They can be purchased here in the Pelam web site and are a lot easier to handle Are you preheating the lantern long enough? If the lantern is not peheated long enough it could be a problem. Kerosene must be preheated long enough to ensure proper lighting. Usually approx 1 minute to 1 1/2 minutes is enough. I am not an expert and i am sure some of the more experienced members will correct me if i have told you something wrong.


    Christop

    hey, Christop. thanks for the answer. I am indeed preheating the lantern long enough, so that's not the problem - but I will try to seal the nipple even more. you're talking about the right height of the needle above the nipple in the closed position. What would this right height (distance) be?
    thanks again

    Woland,
    The needle should be approxamatly 1/2 millimeter. Do not go over 1 millimeter ever. Are you using the rapid fire for preheating or a preheater cup?? Also are you sure the needle you put in did not get damaged after you put the nipple on. Easy way to tell is to look and see if it is sticking out above the nipple in the 12:00 closed position. Do not give up on trying to figure out what the problem is. The finished product is well worth the effort. Trust me on this. A Petromax is an awsome lantern when it is properly functioning. :rauch: So keep me posted and let me know what you find. Is the Petromax 500CP lantern the only lantern that you have?
    Christop

    Hello Woland,
    welcome to the board :welcome:


    Your problem could be caused be various varieties, to the first - better you never use coloured petrol or paraffineoil, the particles of the colour are melting together in the vaporizer to a kind of coal.


    This could be your Problem, did you check your upper Vaporizer? Maybe you'll have to clean it out, because black spots on the mantle do often appear when there is less gasmixture than needed.


    The flames could also come from the coaled inner Vaporizer, because of dirt-particles in your injection - this could be checked by turning the Handwheel 2-3times around (every turn 360°)-called needling, becaose the needle would clean out dirt particles of your injektion. After that, it should run better for some time.


    Maybe the whole inferno is caused by the lower End of the Vaporizer, there is a valve inside the tank that might be no longer working proper.


    To your other Question: Petrol running out of injection after shutdown - when you turn out the lamp by handwheel, a little bit of Petrol is still in the vaporizer - that will cook up because of the remaining heat.
    If it is more, than your vaporizer-valve( inside the tank) need to be changed or adjusted.


    Oterwhise, you should, for switch off, shut the handwheel and open the little screw on your manometer to enlash pressure- when open, re-open your handwheel.
    Remaining petrol would not cook up but rinse back into the tank.


    Maybe, you should check through the whole lantern, because, as you said, you've got it ( her:naughty:) for some years by now.


    Somewhere on the board is a plan for "buid down an up" of the lantern.


    Good luck and best regards Björn :done:

    God created men.
    Sam Colt made them equal!

    hey,
    yeah, the coloured kerosene maybe a problem from what you tell me - it seems logical, that colour is a foreign body in the liquid and it is true, that a layer of black soot covers the upper part of lamp whenever I use it, and maybe it is possible that the same happens in the vaporizer, and then stains the exhaust gases and the mantle. I don't really now, it maybe due to the melted colour particels, even though I always thought, that clear (colourless) kerosene produces black soot as well. Am I wrong? The problem is, that in my country (Slovenia) there seems to be a bit of a problem to attain a colourless kerosene and I have no idea why. The one they sell for lamps and for stoves is green and i can tell it is kerosene, and not some decoration oil or smt. and it's not green for decoration purposes for sure. who knows...
    I don't have my lamp at hand, so I will try putting all the suggested measures into action the next time, and we'll see. also, is it possible to mend the lower end of the vaporizer valve (in the tank) myself if something is wrong with it as you suggest Benz-ihn? thank you and Christop, of course, as well...

    Hi woland,
    it should be possible for you to repair the lower part of the vaporizer yourself (if this is necessary).
    If you screw your vaporizer out of the tank you should replace the small sealing-ring (made from lead) at the tank. For the lower part of the vaporizer: You will find there a filter-cap screwed on - remove this part, there is a small rubber-sealing in, which can be broken or not smooth enough. This can be easily repaired.


    regards,


    fiesie

    Yep, exactly what fiesie said....!


    If you want a graphic, you can try the forums shop-page, there are some Graphics of the whole parts within the repairing- or replacement-parts of Petromax-Lanterns.


    Good luck, :done: Björn

    God created men.
    Sam Colt made them equal!

    Hello there!


    I'm trying to use this thread becouse of the same problem:


    does anyone knows which filter-cap and small rubber Fiesie was talking about (in the post number 7) ?!?
    which are the referring numbers!?


    Thanks in advance,
    Marco

    Ciao


    the reason why I didn't find it is becouse there where no seal! :)
    which are the differences between lead seal and viton one (in the shop)? should I buy the lead seal?


    about #193: have I change this part too?! the rubber is less than 1millimeter...


    Should I check something else?! I already changed the leather washer for pump pistol..



    Grazie mille!!

    the lead seal is the historic and technical correct seal and provides a solid base for the vaporizer for the final assembly.
    the rubber seal is whilst working on the lamp, if you have to unscrew the vaporizer often. you can use the rubber seal more times, the lead seal only once.


    the #193 should be changed too, especially if you have stripped the vaporizer. it´s one of the most important seals on the Petromax.


    and please check the #17 of the pump valve.