Hi all, A few years ago I was gifted a Meva No.1 silent burner stove and just recently decided to move it to the top of the project list. So I joined this site, which is excellent btw, and did a bunch of reading to figure it out. I cleaned up the stove and finally fired it this evening. Full disclosure: I'm a Coleman guy and this is my first kerosene stove. After a few failed attempts and a couple emergency shutdowns I got it to burn fairly consistent but far from perfect. There's a lot of yellow flame and no clean blue flames out of the tiny holes around the top cap. I seem to be getting way too much fuel coming out of the jet so when I give it more than 3 or 4 pumps raw fuel just spits all over the place,... hence the emergency shutdowns. So now the stupid beginner question: is there supposed to be a wick in the tank and into the tube below the spirit cup? If yes, can I buy one or make one? Thanks guys.
@burnt45 There’s no fuel wick in this kind of stove. They do not run at high pressure, so the firing technique is to prime them (protected from the the wind) with alcohol (a couple of minutes) so that the fuel is vapourised as it enters the burner. At this point gas (vapourised kerosene) will emerge from the outer cap of the burner at one or two pumps, which you can then light. Pump a few more strokes until you get a good flame. You should desist from pumping when flamelets lift away from the outer cap. Sooty flames with too much yellow are caused by a number of factors including a loose nipple (jet); the inner or outer caps not sitting flat on the burner; or an enlarged jet in the nipple. Check these options (the enlarged jet last). Cheers Tony
@burnt45 Hi looking at your picture there is flame at the jet which is wrong (underburn) which can quickly destroy your burner . The correct procedure is to prime with alcohol with the pressure release screw open DO NOT PUMP. When the flames have completey gone out close the pressure release screw and give a few pumps, light the white vapour coming from the flame spreader and allow to burn for a minute or so and then pump some more until desired flame is reached. If the flame flashes back to the jet or under the cap Immediately open the pressure release screw and start again. Large yellow flames show neat kerosine coming from jet, release pressure and re-prime. Hope this helps and as Tony says check you have both inner and outer caps present and in place and lastly that your jet is not loose.
Thanks guys, great comments. That underburn pic was just to show what was going wrong, I didn't burn it for long. I've been lighting it exactly as you say, and thank god for the vent screw or I would have been running for the fire extinguisher! I've now snugged up the jet a bit, and checked both caps. The inner cap is minty and straight, but the outer cap is fugly,... someone has done a lot of brazing repair, and it's out-of-round. I tried to get it round again but it doesn't sit very nice on the perforated ring,... it rocks back and forth a bit. As per the new pics, it burns a bit better with no underburn. Should I smooth out the inner side of the cap with a dremel to help disperse the vapour better? So after I do my preheat and I pump once or twice, should I actually see a stream of liquid coming from the jet or should it be vapour at that point? I've tried doing 2 preheat cycles but I still see a stream of liquid... and it's not coming out straight so maybe the orifice got buggered.
Hi well the last flame shot looks better but there should not be a bit of wire inside the flame spreader. Owners sometimes use a bit of wire outside to hold the caps in place and prevent loss hooked through the holes in the burner skirt. The damage to the outer cap may be the result of underburn . Smoothing the inside will not hurt and may improve the flame. Liquid should not come out of the jet and if crooked needs pricking. I would fix one thing at a time so first remove that bit of wire, prick the jet and try to light the stove again. If necessary it is simple to replace the outer cap and/or the jet but the inner cap is specific to the Meva. I think however that the wire is causing the problem as the flame shot looked quite good. I think it is clear vapour coming from the jet which as it condenses becomes white just like water vapour turns to steam but hard to say without seeing it. I hope this helps and I’m sure you will get there in the end.
Further to my last post if it runs reasonably well the flame often improves after 10-15 minutes as the burner gets to normal temperature and burns off old residues, dust, etc.
@burnt45 I agree with @Firestarter. Remove the wire. It may be making the outer cap function improperly. When wire is used to keep the outer cap from falling off in transit, it is placed over the outside of the cap. Cheers Tony
Thanks to Firestarter and Tony for telling me to remove that wire,... definite improvement. Now every one of the little holes in the outer cap show blue flame. So I guess the wire caused the cap to sit up enough that the vapour escaped underneath instead of thru it. In spite of the big yellow flame, I managed to boil 700ml of water in an open container in 8 minutes, I'll call that a success. However it's still a SOB to fire up. I did 3 consecutive pre-heats with methyl hydrate and I still had to shut it down at least 10 times due to the jet flooding me out and fireballing. I'd wait until the fuel was burned off then try again, and finally the jet shot vapour instead of raw fuel. I'm thinking it's too rich, either someone buggered the jet orifice or it's not the correct one. I don't know what size of jet it is, but the Primus pricker that came with it is a #4605... whatever that means. My daily Newb question: Does it matter that I'm using Paraffin instead of actual Kerosene?
I had the same experience with this type of burner. I found that I was pumping too much pressure. pumping two or three times turned out to be enough. After a minute or two, pump twice more. Should the flame become too high (orange) then release the pressure. I now enjoy working with these burners
@burnt45 Progress now to answer your questions ,#4605 is the part no for a Primus 32mm pricker which is the correct one for most 2 pint stoves I assume your Meva will have a 32mm jet. 2450 is the equivalent Optimus pricker. Paraffin and Kerosene are the same thing however there are different grades. Here in the U.K. grade C1 is what I use. Not sure what it is over there. I apologise if I’m stating the obvious but the stove should be filled about two thirds full, no more than three quarters Thanks to @kerophile for the excellent links you can see what your stove should look like running well. So if your stove is not overfilled or over pressurised it looks like a jet change would be the next step
Bertran: I have quickly discovered the same thing; 1 or 2 pumps to light is plenty. The last time I had it running for 20 minutes or so, I experimented with pumping it up 2 or 3 more times then slowly bleeding off some pressure to see if there was a sweet spot,... but still the big yellow flame. It reminded me of tuning a carburator on an old ski-doo. Thank you Firestarter for the jet info,... I will be ordering a new one. This stove will spend most of it's time on display in my shop, but I like having things in working condition. Not to mention it's a great burner for cooking up a pot of corn outside! So in Canada we can buy Paraffin or Kerosene. They're typically side by side on the hardware store shelf. Usually Kero is in a gallon jug and Paraffin is in a 750ml or litre bottle. Also on the Paraffin bottle it will almost always say "Lamp oil",... people use it for that as there is barely any smell like kerosene. Now depending who you ask, some say Paraffin is a more refined version of true kero. I've never done a comparison, I just buy Paraffin because I burn it occasionally in lanterns at my camp. I appreciate all the advice guys,... I'll post a pic when I get this baby burning blue! PS: I may have been bitten by this damn stove bug,... I just found a local guy that's selling a Svea 123 and an Optimus 8R......... having a hard time talking myself out of it.
Hi the 2 stoves you mention are both ones on my wish list but money and space prevent me buying more stoves at present. Lamp oil is not good for stoves or pressure lanterns It is less volatile and does not burn so well . It is good for wick lamps as low odour. Kerosine has a flash point of about 36C whereas lamp oil is 65C I bet your stove would run much better on kerosine. Here in the U.K. we have lamp oil and C1 kerosine/paraffin which is low odour and low sulphur and C2 which is central heating oil for oil boilers which is sootier and not intended for indoor use. I would try kerosine before ordering a new jet as this may be the problem! @burnt45
Interesting re Canada. In the States I've never seen any fuel labeled "paraffin". Maybe a residual Britishism up there. Here, "paraffin" means the wax, only.
That's interesting, I'll go get some kero tomorrow. Here's what I've been using: I notice now the lamp oil says "paraffin based". Methyl Hydrate is our version of wood alcohol or denatured alcohol. No idea if the chemical properties are the same, but it burns nice.
